Hydronic Radiant Heating

When designing a home, it is important to consider early in the process what type of climate control system the home will be using. Mechanical systems used for heating and cooling work best when they are properly sized, thoughtfully laid out, and have adequate space for all the components.

There are many options for heating and cooling a home. Many homeowners these days are opting for hydronic radiant heat systems, and we get a lot of questions from our clients about radiant heat systems and how best to configure them.  Radiant heat is a great, energy efficient choice for homes where heating is the primary concern and cooling is secondary.

Hydronic Radiant Heating

Unlike forced air heating systems, radiant heating warms the objects in a space, not just the air. Because of this, the space will feel warmer and the ambient temperature can be kept lower than it would be in a space that is heated with warm air.  Other benefits of radiant heat are the lack of moving air that can transport dust and allergens, and the ability of radiant heat to maintain an even temperature without noticeable fluctuations.

Hydronic radiant heating uses a central boiler to heat a fluid that is then circulated through piping concealed in the floor system.  The choice of floor system is a major determinant in the performance of a hydronic radiant system, but the choice of floor system should not be based only on what type of heating the house will utilize.

The best radiant heat systems use a concrete floor slab as a thermal mass (see related concrete slab vs. wood framed floors).  Heavy duty plastic tubing is embedded in a slab that is insulated both on the perimeter and on the underside. The amount of insulation depends on the local climate, the level of efficiency desired, and the budget.  The biggest advantage of this system is the substantial thermal mass of the concrete slab, which will store and radiate heat over an extended period of time.  The slab will also double as a collector and storage medium of any passive solar gain. On the flip side, the slab will take a while to heat up, so this type of system does not lend itself well to turning the heat down during periods of inactivity or absence.

Leaks and damage to tubing that is encased in a concrete slab can be costly and difficult to fix, but thankfully they almost never occur.  Problems due to tubing failure can be mitigated by making sure the tubing is thoroughly leak tested and the slab subgrade is well compacted granular material.

When a concrete slab floor is not practical, radiant heat tubing can be embedded in 1½” or more of lightweight concrete or gypcrete poured on top of a wood framed floor.  This is often done on homes that have hydronic heat on upper floors or where a crawl space and wood framed floor is necessary.  Since a 4” concrete slab is too heavy to be supported by a wood framed floor, a thinner, lighter slab is used.  It has significantly less thermal mass, but does provide some heat storage capacity and also helps dampen floor vibrations common with wood framed floors.  Floor framing has to be more substantial for this type of application than it would be for a floor that doesn’t have to support as much weight.

Gypcrete

For radiant heat applications where a wood framed floor is preferred or required and gypcrete overlayment is not used there are a few different options.  Warmboard manufactures a plywood subfloor sheathing that has integral channels milled into it that allow radiant heat tubes to sit below the top of the subfloor.  The channels are clad with sheet aluminum that radiates heat upward into the living space and makes for rapid warming of the floor above.  In this sense, it outperforms the concrete embedment systems, but it lacks the thermal mass and ability to moderate temperature fluctuations.  Warmboard is relatively expensive, but by most accounts it functions well and is a viable alternative when concrete or gypcrete is impractical.  Misplaced nails or dropped tools can easily damage the tubing, so pressure testing is required before covering and after flooring has been installed.

The staple up radiant tubing application is the least expensive and easiest system to repair or retrofit.  As a trade off,  it is also the least efficient and easiest to damage.  Staple up systems involve installing the tubes on the underside of the subfloor between floor joists.  The tubes are held in place by staples and sometimes backed with foil faced rigid insulation or installed with integral metal heat transfer plates.  In order to be reasonably efficient, a staple up system needs to have more than code required insulation in the joist bays, and shouldn’t be used where floors are cantilevered out beyond heated space below because of the potential for condensation.

Staple-up radiant heat is the least efficient.

For more on floor system options to use with hydronic radiant heating, see our article on concrete slab vs. wood framed floors.

Tom Russell, Project Architect, LEED AP

Hendricks Architecture specializes in custom mountain style homes.  Our homes have been featured in Timber Home Living, Mountain Living, Green Building and Design, Cowboys & Indians, Cabin Life and other publications.  We’re located in Sandpoint, Idaho.  Subscribe to Hendricks Architecture’s Blog

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Energy Efficient Cabin Under Construction

An energy efficient small mountain cabin is currently under construction on a steep site overlooking Bottle Bay, east of Sandpoint on Lake Pend Oreille.  Scott Schriber of Selle Valley Construction and his crew are hard at work on this 1700 square foot eclectic cabin that promises to fulfill the owners long held dream of moving to the area and living in a high performance home populated with reclaimed fixtures and funky furnishings.

This highly energy efficient three bedroom cabin, designed by Hendricks Architecture, is being constructed using the Remote wall system, which utilizes a thick layer (or several layers) of exterior foam insulation sheathing to minimize or eliminate thermal bridging.  Scott is a big proponent of the system, and it was an easy sell to the owners who knew they wanted a high performance energy efficient home.

Cabin Side Elevation

This cabin will most likely qualify for gold level certification under the National Association of Home Builders Green Standard.  Selle Valley Construction has built several Green Certified homes, and Scott was a driving force in choosing the innovative construction systems that are employed in this cabin. In addition to the remote wall system, this cabin is being built using advanced framing techniques, raised heel trusses, and locally sourced cedar siding.  The design called for rusted corrugated steel siding used as a wainscot around the entire cabin, and Scott’s wife Barb Schriber worked with the owners to find reclaimed material for this application.

The owners have done a lot of work on their own, collecting numerous old plumbing fixtures, doors, and the like to use in their dream cabin. While this project does rely on some new technologies and devices to help reduce its impact, part of the green strategy is to utilize recycled or reclaimed goods as much as is practical, especially when it contributes to the eclectic character they are striving for.

The cabin has a large deck that faces the lake, as well as a covered screen porch for enjoying fresh air and early summer nights when the weather or mosquitoes can make being outside unpleasant. The screen porch was one of the owner’s favorite parts of the house, and despite a tight budget, they insisted on keeping this vital outdoor living space. The location of the cabin was forced by setbacks and steep topography, and as a result the deck and screen porch hover dramatically over the forest below.

Cabin & Deck Under Construction

Inside, a loft above the private spaces is open to the vaulted Great Room/ Kitchen below. The loft is primarily intended as a playroom for the grand-kids, but was designed with a couple opposing shed dormers to provide natural light and an area with enough headroom to house bunk beds. A heat recovery ventilator in a closet above the entry will help draw heat to the loft from the ductless heat pump located on the south wall of the great room. The heat pump and a wood stove in the great room should easily heat the entire cabin.

We are seeing a lot of interest in smaller energy efficient homes in North Idaho. If a new cabin or mountain home is in your future, we would love to talk to you about helping to make it a reality.

Tom Russell, Architect LEED AP

Hendricks Architecture specializes in the design of timber mountain style homes and cabins.  Most of the homes we’ve completed are in mountain resort areas throughout the West.  If you are interested in a mountain home, or you have any other inquiries, please contact us.

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The National Green Building Standard

The green building movement has generated quite a following in the last 5 or 10 years, and what used to be a somewhat fringe idea is now becoming part of mainstream culture. Advertisements for products and services across the spectrum are full of sometimes dubious claims of how environmentally friendly they are, and efforts are being made in many industries to create a metric to quantify how “green” something really is.

The building industry has been a leading force in the establishment of meaningful rating systems for measuring the environmental impact of common materials, methods, and design practices used to create modern buildings. The LEED rating system was developed in 2000 by the U.S. Green Building Council, and soon became the industry standard, perhaps because it was the only standard. It has evolved from a broad scope that attempted to encompass all aspects of building construction into a suite of specific rating systems that target specific project types.

In 2007, the International Code Council (ICC) and the National Association of Home Builders (NAHB) partnered to create a nationally recognizable standard for measuring sustainable building practices called The National Green Building Standard. It provided a much needed tool for comparing the relative merits of single and multi-family homes built using established or innovative products and practices. Since it is specific to the residential sector of the construction industry and a companion document to the ICC suite of model building codes, many builders and homeowners are choosing to pursue certification under the National Green Building Standard.

The Green Building Standard is similar to LEED in many ways. Both utilize a point system that is used to achieve one of four different levels of certification. In the National Green Building Standard, the levels are Bronze, Silver, Gold, and Emerald. Points are earned for employing green building practices that fall into categories covering the basic tenets of sustainable design and construction:

1)      Site selection, design, & development

2)      Resource Efficiency

3)      Energy Efficiency

4)      Water Efficiency

5)      Indoor Air Quality

6)      Owner education on systems operation and maintenance

7)      Innovative practices

In both the LEED and NAHB rating systems, an independent verifier is used to determine a project’s level of achievement.

In general, the NAHB Green Building Standard provides rewards for practices that exceed the basic requirements of building codes, especially as they relate to minimum insulation levels, plumbing fixture flow rates, and ventilation requirements. Emphasis is placed on high efficiency heating / cooling, minimizing generated waste, using durable, renewable, salvaged or recycled materials, and avoiding products that contribute to poor indoor air quality or have adverse environmental impacts.

At Hendricks Architecture, we have designed a couple homes recently that will be seeking certification under The National Green Building Standard.  Scott Schriber of Selle Valley Construction will be building both of them, and he has constructed several NAHB certified green homes in the last few years. He estimates that it costs an additional 3%-5% upfront to build a home that achieves Green Standard certification.

A home designed to achieve certification under the National Green Building Standard

Our experience has been that when clients are considering if they should build a high performance/ low impact home, upfront cost is almost always a factor. When trying to decide if  “going green” makes financial sense, it is important to remember that a home built to The National Green Building Standard (or other rating systems) will benefit from substantial long term energy and maintainace cost savings, improved indoor air quality, and enhanced resale value. Financial considerations aside, many homeowners are opting to build high performance green homes simply because they value the peace of mind that comes with creating a healthy, durable place for their families to live.

Tom Russell, Project Architect, LEED AP

Hendricks Architecture, mountain architects in Sandpoint, Idaho.  Subscribe to Hendricks Architecture’s Blog

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New Energy Code Requirements for Insulation

As of January 1, 2011, many states, including Idaho, adopted new energy code requirements with the 2009 International Energy Conservation Code (IECC). The new code has stricter requirements for the energy efficiency of the building envelope (a technical term for the part of a building that keeps the interior warm, dry, and comfortable). The new code requires a roughly 8-10% upgrade in building thermal efficiency from the previous code.

The biggest changes affect insulation values in ceilings, below grade walls, and to a lesser extent, above grade exterior walls. The insulation requirements vary within 8 different climate zones.  North Idaho and much of the Intermountain West are in climate zone 6, which has only slightly lower insulation requirements than zones 7 & 8. Zones 7 & 8 encompass the very coldest parts of the country.

Here’s a quick overview of the new requirements:

• Ceiling insulation values have been increased from R-38 to R-49.  (The R-value is a measure of thermal efficiency – the higher the number the more efficient the insulation).  This is significant and potentially costly to homeowners, especially if they want vaulted ceilings. Typical roof framing members are not deep enough to accommodate enough conventional fiberglass insulation to achieve this high R-value. There are options that can be employed to meet this requirement and still have vaulted ceilings.

1. Use deeper rafters. This is potentially expensive, an inefficient use of resources, and generally not recommended unless structural requirements dictate it.
2. Use urethane spray foam insulation, which has a much higher R-value per inch. This product is more expensive than fiberglass insulation, but is an excellent air seal and eliminates the need for venting, which is sometimes difficult on complex roofs.
   

   Urethane spray foam insulation

3. Use fiberglass insulation in the rafter space, and then a continuous rigid board insulation on either the ceiling below the rafters or on the roof above the sheathing. This reduces thermal bridging, which is a major source of heat loss in stick frame construction. Depending on the application, it may be better to put board insulation on the interior; putting it on the roof is physically easier but makes attaching some types of roofing problematic.
   

   Rigid Board Insulation

The code does allow for some R-value reductions if certain details are used, and there is an allowance for a maximum of 500 S.F. of vaulted ceilings with R-38 insulation value, subject to some restrictions.

• Basement wall insulation values have been increased from R-13 to R-19. These numbers are for insulation in wall cavities, if continuous board or spray foam insulation is used R- 15 is required. This accounts for the reduction in heat loss through thermal bridging, as mentioned above. One implication of this is that basement living space will potentially be reduced because walls need to be thicker to accommodate more insulation. Use of an ICF foundation system is an effective way to achieve this R-value without losing interior space.
  

  ICF Foundation

• Exterior wall insulation value has been increased from R-19 to R-20. This is significant because conventional fiberglass batt insulation is not able to achieve R-20 in a 2 x 6 wall. As an alternative, the code allows for a cavity insulation value of R-13 if a continuous board or foam insulation of minimum R-5 is used as a supplement. This is, again, an acknowledgement of the value of reducing thermal bridging. Urethane spray foam insulation can easily achieve R-20 in 2 x 6 stud cavities.

The new IECC has upped the ante for reducing building energy consumption, and future versions of the code promise further improvements. I have always been an advocate for maximizing the thermal performance of any new building, and hyper-insulating is a very effective means of achieving that goal. Money spent up front in insulation will be rewarded through reduced energy costs, smaller mechanical systems, and enhanced comfort levels for building occupants.

Tom Russell, LEED AP, Project Architect

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Deconstruction vs. Demolition

Recently I read an article in the Seattle Times Home and Garden section about deconstruction versus demolition, both of which I’ve had experience with as an architect.  “On average, more than 75 percent of a home can be reused and recycled”, said writer Stacy Downs.

When you hear the term “tear down”, most homeowners simply have the contractor tear down a home, take it to the dump, and start a new home with new materials.   The art of deconstruction, where a contractor takes the time to disassemble the light fixtures, cabinetry, doors, door handles, plumbing, and other parts of the house, is becoming more and more in vogue.

Some of your plumbing and light fixtures can be reused on your new home.  Your original concrete foundation, garage floor, basement, patio, driveway and brick chimney could be  crushed and used for your new home’s foundation backfill, potentially saving you thousands of dollars.

In the case of the mountain style homes we design, recycled timbers are extremely valuable.  Not only are these rustic timbers physically beautiful, but they are also sometimes bigger and longer than those commercially available, not to mention the strength of the old-growth wood.

I designed a new home a few years ago in Bellevue, Washington where the old home was deconstructed.  It was the homeowner’s idea, and at first I had thought they would lose money in the deal.   Deconstruction is much more labor intensive and the costs of deconstruction are initially higher.  However, if you’re willing to wait until after taxes, you could actually earn money if you have it appraised for the value of the salvageable structure.

Not only could you get tax benefits, you could also get extra LEED points, as well as help ease the minds of the environmentally conscious.  More than 30% of waste that goes into landfills consists of building materials.  For more info, or to purchase recycled goods, look up your local Habitat for Humanity ReStore resale outlet.  Proceeds help your local Habitat affiliates fund the construction of Habitat homes within your community.

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John Hendricks, AIA Architect

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Residential Heating Options

As architects, our clients are always asking for guidance on what type of heating or cooling system will be best for their home. The answer is not a simple one, and making a decision usually involves weighing a combination of personal preference, initial vs. life cycle costs, practical constraints, and climate considerations.  There are a lot of residential heating options out there, and deciding which one is appropriate for your situation will not only impact your future utility costs, but also your level of comfort and satisfaction with your home.

Some of the practical considerations that weigh in on the decision are:

1.   Climate

• If you live in a hot climate, cooling will be the primary consideration. Heating will be a secondary concern and may only be required very occasionally.
• In most areas of the country, both heating and cooling are required, depending on the season. Choosing a system that does both efficiently is important
• Some mountain environments don’t require cooling, or natural ventilation can be used to control the comfort level and mechanical air conditioning is not necessary.

2.   Availability of energy sources

• Depending on location, electricity, natural gas, or other public utilities may be unavailable or prohibitively expensive.
• Renewable energy sources may be available and cost effective to utilize (solar in the Southwest, wind on the coast, geothermal near a large water body)

3.   Relative cost of energy

• Electricity rates vary significantly
• Natural gas is typically a good value, but not always available
• Heating oil and Propane are usually delivered by truck to your site. They may or may not be less than electricity, but delivery can be subject to weather and seasonal accessibility challenges.

4.   Initial costs vs. life cycle costs are always a consideration. In general, the systems that cost the most to operate are the least expensive to purchase and install. A system that uses very little or no energy may be expensive to buy, but might pay for itself in a reasonable time and end up saving money in the long term. Energy efficiencies of the different systems vary greatly.

5.   Personal preferences vary

• Some people find moving air (especially cool air from air conditioning) to be uncomfortable.
• Individuals with allergies or respiratory ailments may be affected by forced air systems, which tend to re-circulate dust and other airborne contaminants.
• Some systems are better for zoned comfort, allowing inhabitants to vary temperatures in different areas of the home.

6.   Space requirements may be an issue

• Duct systems may need dropped ceilings, soffits, and vertical chases
• A/C condenser units need to be outside and near mechanical room
• Hydronic systems work best in concrete floors or with a gypcrete overlay
• Baseboard heaters take up floor space and affect furniture layouts

Here is an overview of the commonly utilized systems and their pros & cons:

Electric resistance heat (baseboard, fan forced wall heaters, forced air)

Pros-

• Inexpensive upfront cost
• Easy to control heat levels in individual rooms
• Doesn’t require gas service
• Can be turned down during the day to save energy

Cons-

• Inefficient and expensive to operate
• Requires a separate system if A/C is desired
• Dry heat, requires humidification in most climates
• Most systems don’t utilize outside air, so a separate air exchange system is required
• No heat during power outages

Best use-

Not recommended unless gas service is unavailable and low cost is top priority.

Electric heat pump: (forced air system with heat exchanger, basically an A/C system run in reverse)

Pros-

• Doesn’t require gas service
• High efficiency
• Fast response – changes the ambient air temperature quickly
• Can be turned down during the day to save energy
• Moderate initial cost
• Can be retrofit to existing forced air system
• Works equally well for heat & A/C

Cons-

• Requires a condenser unit for each zone
• No heat or cooling during power outages
• Requires a duct system
• Re-circulates inside air

Best Use-

Where gas is unavailable or expensive. Heat pumps are best used where heat as well as A/C are necessary.

Gas fired forced air: (conventional furnace, with or without A/C)

Pros-

• Natural gas is usually inexpensive relative to other sources
• Can be high efficiency depending on equipment and design
• Moderate initial cost
• Fast response – changes the ambient air temperature quickly
• Can be turned down during the day to save energy
• A/C function is optional, and can be upgraded for minimal cost
• Popular system, so repairs are usually fairly easy and inexpensive

Cons –

• Gas availability varies
• If required, propane and heating oil are expensive and require a tank
• Requires a duct system
• Re-circulates inside air
• Gas leak and Carbon Monoxide hazards exist
• No heat or cooling during power outages

Best Use-

When natural gas is available and inexpensive, space required for ducts is not an issue, and initial cost is a primary consideration.

Hydronic radiant heating: (heated liquid circulated through a network of concealed piping)

Pros –

• Heats objects rather than the air, so it is more comfortable heat.
• No re-circulated air, so indoor air quality is better
• No visible appliances or registers
• No sensation of moving air
• Floor, furniture and other objects are always warm / cool
• Boiler can be used for domestic water heating as well
• In rare cases, wood can be a fuel source rather than gas

Cons –

• Higher initial cost, moderate operating cost
• Slow response time – can take several days to change the temperature significantly
• Can’t be turned down for short time periods
• Cooling function doesn’t work as well as forced air – condensation can be an issue
• Retrofitting, modifying or expanding system can be difficult
• Needs concrete, gypcrete, or other thermal mass  to work well
• Requires ventilation system to exchange air

Best Use-

When the highest level of thermal comfort is desired. Ideal system when heating is the primary function, cooling is secondary, and short term temperature fluctuation is not required.

Installing Electric Floor Heating

Electric Radiant Heat: (Similar to hydronic, except for the following)

Pros –

• Less expensive initial cost
• Works best with thermal mass, but can be used without
• Can be used for small areas to supplement other systems
• Can be supplemented by solar photovoltaic panels

Cons –

• Expensive to operate
• No cooling function

Best Use-

When the comfort of radiant heat is desired, and gas is unavailable or expensive. Electric radiant is popular for small areas (bathrooms, kitchens, mudrooms) in homes that have non radiant systems.

Fireplace or wood stove

Pros-

• Add to the ambiance of a space
• Wood heat feels good, similar to radiant
• Fireplaces and stoves can be gas or wood burning
• Visual as well as functional benefit
• Provide heat during power outages

Cons-

• Fireplaces and stoves take up floor space
• Firewood requires storage space and can be messy
• Wood burning appliances require cleaning and maintenance
• Potential fire hazard
• Aren’t effective at circulating  heat to large spaces

Best Use-

Fireplaces and woodstoves are great at supplying supplemental heat, but are not always feasible as a primary heat source. They are common in mountain homes, and can be a huge asset during prolonged power outages.

Some alternative energy sources can be used with heating and cooling systems to cut operating costs and environmental impacts. Some of the options that are available include:

Solar hot water – Solar Panels (usually roof mounted) can supply heated water to hydronic systems. Limited to cooler climates that have predominately clear skies.

Solar Photovoltaic – Solar cells in a variety of forms generate electricity that can be used to supply electric heat pumps, radiant or resistance heating systems.

Geothermal – Captures heat from the earth or large water bodies to supply hydronic systems or electric heat pumps. Despite what common sense would imply, heat can be extracted from earth or water that is at relatively low temperatures (32-55 deg Fahrenheit) and used to heat water or air to temperatures in the human comfort range.

Wind or moving water can turn generators that produce electricity. These systems are less common, but if the environment you live in has one of these energy sources, it can be utilized to heat and cool a home.

Upfront costs for alternative energy systems tends to be higher than for conventional public utility powered systems, but the energy savings can be substantial. It is worth considering the cost and environmental benefits that alternative energy systems can provide when making the decision of which type of climate control system to use in your home.

We have seen many of these systems installed in the mountain homes we design, and can help you make informed decisions on which system will be best for your project. We try to stay informed of the best technologies because we know how important the climate control system is to the proper function and overall enjoyment of a quality home.

Tom Russell, LEED AP and John Hendricks, AIA Architect

Hendricks Architecture, mountain architects in Sandpoint, Idaho.

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Fireplace Options

In the Mountain West, where we do most of our work, the majority of homes have some type of fireplace. Some statistics suggest that more than 75% of home buyers in these areas want a home with a fireplace. We specialize in mountain architecture and I can’t remember a home that didn’t have a fireplace of some type.  Having once spent several days without heat during a mid winter storm induced power outage, I can be counted among this majority. Fireplaces (or heating stoves) provide a focal point and gathering place that can be as aesthetic as it is functional.

Lake Quinault Lodge Masonry Fireplace

Fireplaces and heating stoves come in a variety of shapes, sizes, and styles. For those who want some type of fireplace in their home, there are a number of things to consider when making the choice of which is best for you. Factors such as desired function, type of application, space requirements, cost, and willingness to do the work required for burning wood should be considered.

If you are considering wood burning, check local regulations to make sure it is allowed. Some municipalities with air quality problems restrict or don’t allow wood burning, including many resort towns that are located in mountain valleys with winter temperature inversions.

Available options range from traditional open masonry fireplaces to modern high-efficiency airtight wood or gas stoves that are as artistic as they are functional. Following is a broad overview to present some of the choices.

The Lake McDonald Lodge masonry fireplace at Glacier National Park. The opening is about 6'-6" high.

Masonry Fireplaces – The most traditional (and most expensive), this is the choice for those seeking authenticity and a powerful presence. Masonry fireplaces have a high thermal mass, which works well to radiate heat when it is kept warm, but can have the opposite effect when it is cold. Open face fireplaces also lose most of the heat they produce up the chimney, and in some cases they draw warm air out of the room and send it up the chimney as well. A tight fitting damper  can help control heat loss when the fireplace is not in use.

Masonry fireplaces require the most space, and are often continuous from the foundation all the way to the top of the chimney.  A substantial foundation is required to support the weight of a masonry fireplace, so adding one to an existing home is often not practical.

One type of masonry fireplace, the Rumford style, is designed specifically for heating, and is the most energy efficient open face fireplace for space heating.

A Precast Masonry Rumford Style Fireplace with Custom Surround by Pacific Construction.

A fairly recent advance in masonry fireplace technology is the development of precast firebox and chimney components, which speeds up installation time and offers a UL listed system. Many of these are of the Rumford style.  If you aren’t going to burn wood, building a full masonry fireplace is probably not practical, though masonry fireplaces can and often are equipped with a gas supply for possible future conversion or for a gas log lighter.

Prefabricated Fireplaces – One alternative to the traditional masonry fireplace is to use a prefabricated firebox which can be used with a stone or brick veneer surround to resemble a true masonry fireplace. The construction required for these “insert fireplaces” is much less complicated (hence less expensive) than true masonry, and prefabricated units are more airtight and efficient. They can be equipped with fans that circulate air in a confined space around the firebox and blow it into the room (and in some cases throughout the house) to enhance heating. It is possible to in some cases to retrofit an existing fireplace with a new insert to upgrade its efficiency. Prefabricated fireboxes are available in both gas and wood burning versions, with some models able to do both.

Prefabricated Gas Fireplace with Custom Surround.

Wood or Gas Stoves – These are free standing appliances that are typically much more efficient at heating than any type of built-in fireplace. They require less space, less fuel, and come in a wide variety of styles from very traditional to ultra modern. It is possible to use wood or gas stoves as a primary heat source if they are well located and properly sized, but a wood stove would require a backup system for extended absences and for individual control of private spaces. Gas stoves are usually thermostatically controlled and have blowers on them to increase heating effectiveness. Wood stoves are especially effective if they are close to a large thermal mass such as a masonry wall or concrete slab. Some stoves are clad with slabs of soapstone or a similar material that stores and radiates heat over long periods of time.

Avalon Wood Stove

The decision to burn wood or gas is a personal one, unless you live somewhere where the air quality regulators have already made this decision. Gas is more convenient, doesn’t require storage space, is available just about everywhere, and is cleaner.  The cost of gas versus wood depends on the prevailing prices in your area and the efficiency of the device you are using.

Nothing beats the ambiance of a real wood fire, but this pleasure isn’t without its costs. Wood requires storage space, it’s messy, contributes to air pollution, and it requires work on the user’s part. Even if you buy wood and have someone stack it, someone needs to move it to the fireplace, start the fire, and keep it burning. If you are equipped and willing to cut your own wood, the cost is minimal but the effort is significant. As the saying goes, firewood heats twice – once when you burn it and once when you produce it.

Tom Russell, LEED AP and John Hendricks, AIA Architect

Hendricks Architecture, mountain architects located in Sandpoint, Idaho.  Visit our portfolio for examples of some of our recently completed custom projects.

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Energy Efficiency

At Hendricks Architecture, we specialize in the design of mountain style homes and cabins.  We try to make these as energy efficient as possible to save homeowners on long term heating and cooling costs.  We educate them on the practicalities, costs and benefits of energy efficiency throughout the design process.

According to Residential Design & Build Magazine, 2008′s most asked for feature in a house was energy efficiency.  Currently, Americans use approximately 25% of the world’s energy, and roughly 21% of this is consumed in our homes.  Whether we knew it or not, energy efficiency has always been at the forefront of the green and sustainable movements, and is an important part of the LEED process.  As architects, we are committed to doing our part to promote and implement energy efficiency in the homes we design.

There are numerous ways that energy efficiency measures can be incorporated into a new or existing home, and often these measures will also enhance the appearance, functionality, and resale value of a home. Some of the strategies are listed below.  This is not an exhaustive list but an overview of readily available measures that we can use to enhance the energy efficiency of your home. Many people think  adding energy saving measures to a home will initially cost more, and in many cases this is true. In some cases, just making the appropriate design decisions can save energy and not cost any more. It is important to measure additional first costs against long term savings in energy costs, and consider that no one is predicting cheaper energy costs in the future.

DESIGN AND EMBODIED ENERGY

Probably the most fundamental step in creating an energy saving home is to design it for space and functional efficiency. Minimizing non usable space (hallways are one example) and creating spaces that can serve more than one function like Guest/ Exercise or Laundry/ Mud rooms can reduce the overall building area that needs to be heated or cooled. Open plans tend to feel bigger than they are, and save space that would have to be taken up by walls, doors, etc. A good reference for these strategies is Sara Susanka’s “The Not So Big House”.

It is also worth considering the energy use that goes into everything used in the construction of a home. Materials require energy to manufacture, package, store, deliver, etc.  Almost every decision made during the design process has some impact on the energy use of your home.

SITING, ORIENTATION, & MASSING

A home should be located on its site to allow access to the sun, protection from prevailing winds, minimize site disturbance, and use natural elements to provide shading and shelter. Stacking a building’s spaces whenever possible reduces the footprint and the surface area through which heat can escape. Below grade spaces benefit from the relatively constant 50 degree temperature of the earth, reducing or eliminating cooling cost during the summer.

WINDOW DESIGN AND DAYLIGHTING

Windows serve several functions in a well designed home. Besides framing views and providing a connection with the outdoors, windows allow natural light to enter, provide free ventilation, insulate against heat loss, and help heat indoor spaces when exposed to direct sunlight. Windows are a crucial element in a home’s design and function, and should be carefully sized, located and detailed. Windows are the weak link in a buildings thermal envelope, so it is important to select quality windows with a low U value.

Use clerestory windows to help bring in light

Placing windows to provide ample daylighting will save on lighting costs and the number of fixtures needed. Locating windows to take advantage of solar exposure will reduce heating costs and HVAC equipment required. Direct sunlight does not make for good daylighting, primarily because of glare. The best daylighting utilizes reflected or indirect light from transom, clerestory, or north facing windows. Skylights and solar tubes can be used to provide daylight to interior rooms.

ROOFS, OVERHANGS, AND SHADING

A roof should be designed to shade windows that are exposed to direct sunlight in the summer months. Because the sun is lower in the sky in the winter, roof overhangs should be sized to allow direct sunlight to enter the windows during winter months, maximizing solar heat gain to offset heating costs. On building facades where overhangs are not able to provide shade (gables, etc.), pergolas, awnings, or other shading devices should be considered.  Devices that shade lower windows and act as a light shelf for upper windows are particularly effective.

Providing broad overhangs reduces summer heat gain, yet brings in the winter sun.

A house’s roofing material also affects energy consumption. Lighter colored or reflective roofing reduces heat gain, and a well ventilated or cold roof will help keep attic spaces cooler, reducing cooling costs.

INSULATION AND THERMAL MASS

It is well know that the better insulated a house is, the more energy efficient it will be. Building codes dictate minimum insulation values for all new construction. Any insulation value beyond the minimum required will be money well spent, especially in roof/ attic spaces where most heat loss occurs. Several insulation products are available that can provide enhanced R-values and provide a tighter building envelope. It is worth considering spray applied foam insulation, blow in blanket, or rigid sheet insulation rather than conventional fiberglass batts.  Snow actually adds insulation as well, though is not recognized by building departments.

Spray applied foam insulation.

SIPS panels are also an energy saving system that can be used in lieu of conventional stud framing. In stud/ cavity wall systems, thermal bridging occurs that allows heat to pass through studs that contact exterior materials. SIPS panels have a solid sheet of rigid insulation sandwiched between plywood sheets, and no thermal bridging occurs. They are commonly used on roofs and for wall systems in post and beam construction.

SIPS Panels

Thermal mass is the ability of a material to absorb and store heat that is radiated slowly. Materials like concrete, stone, brick, and water all have a high thermal mass.  A well placed thermal mass will absorb solar radiation or heat from a fire, and radiate it slowly to keep a space warm overnight or for several days.  Concrete or gypcrete floors can be heated by solar or gas fired hydronic systems to provide an even heat that feels warmer than heated air at the same temperature.

NATURAL VENTILATION

Operable windows, ceiling fans, and design that utilizes “stack effect” can all be used to passively cool a space, saving energy that would be required by A/C systems. Ceiling fans can be used in rooms with vaulted ceilings to circulate heated air that collects in the peak of the ceiling. Night venting (operating outside air ventilation systems overnight) can also be used to cool a space without using excess energy. Operable windows in bathrooms will also save energy by eliminating the need for exhaust fans when weather permits.

HVAC EQUIPMENT AND APPLIANCES

Heating and cooling equipment are available in a wide range of efficiencies and types. Choosing high efficiency equipment that is Energy Star certified, using insulated duct systems, programmable thermostats, and creating multiple zones for heating & cooling are simple energy saving strategies.

If you live in an area where gas is not available, heat pumps are much more efficient than electric resistance heating. Radiant heating systems with a high efficiency boiler are generally more comfortable and efficient than forced air systems, but are best used in homes that are regularly occupied and should be supplemented with ventilation systems. If a home is used only occasionally, radiant heat may not be the best choice from a cost standpoint, as it takes much longer to raise the temperature of a home to comfortable levels. If you are considering air conditioning with a radiant system, remember that you will be installing two systems since A/C requires a network of ducts to distribute cooled air.

Appliances (especially refrigerators, freezers, and ice makers) consume significant energy. Buying Energy Star appliances are a good way to increase the energy efficiency of your home at minimal extra cost.

We would love to talk to you about ways to increase the energy efficiency of your current home, or to help you design a new home that utilizes these energy saving strategies.

Tom Russell, LEED AP, Project Manager

Hendricks Architecture, mountain architects in Sandpoint, Idaho.

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LEED Accredidation

Tom Russell of Hendricks Architecture recently became a LEED AP, or Accredited Professional. LEED Accredited Professionals have, according to the United States Green Building Council (USGBC), “demonstrated a thorough understanding of green building techniques, the LEED Green Building Rating System, and the certification process.” The USGBC is a non-profit organization that certifies sustainable businesses, homes, hospitals, schools, and neighborhoods. USGBC is dedicated to expanding green building practices and education, and its LEED® (Leadership in Energy and Environmental Design) Green Building Rating System^TM.

The LEED certification process has several rating systems that are specific to different building types and project scopes. LEED for Homes is a fairly new product that was launched in January 2008, after a few pilot versions. It promotes the design and construction of high performance green homes. By using a standardized documentation system, LEED for Homes assures owners that their home has meet rigorous criteria for energy efficiency, occupant health, and minimized environmental impact.

The conventional wisdom is that building a green home or doing a green remodel is much more costly. While in many instances this is true, it is not always the case. It is important to consider long term costs when comparing green building to more conventional construction. First costs can often be offset by long term savings in energy use, maintenance, and reduced equipment needs. The USGBC contends that the net cost of owning a LEED home is comparable to that of a conventional home. It is also worthwhile to consider the intangible benefits of a green home, things like improved health, a cleaner environment, and less dependence on conventional energy sources.

For clients interested in achieving LEED certification for their projects, it is important to have a LEED AP involved as part of the design/construction team. They can help guide you through the certification process, which can be complex and time consuming. Having a LEED AP involved also gains your project a point towards certification.

For homeowners interested in a home that is “built green” but not LEED certified, it is always an option to employ green strategies, products and technologies without going through a certification process. While LEED certification offers assurance of a buildings performance, it is possible to have the same level of performance without being certified. For those considering resale value, LEED certification would likely add value to any piece of real estate because it is a verifiable standard that is recognized nationwide.

For any of our clients interested in building a green home or doing a green remodel, we have the knowledge and expertise to assist you. Whether you are going to pursue LEED certification or you simply want a healthy, energy efficient, low impact home, we would love to talk to you about achieving your goals.

Tom Russell, Architect, LEED AP, Hendricks Architecture

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John Hendricks, AIA Architect • Architecture, Planning, Construction Management
418 Pine St, Sandpoint, Idaho 83864 • T 208.265.4001 F 208-265-4009 • john@hendricksarch.com