A: Our method of building High Performance Homes, "The Systems Approach"
We employ a "systems" approach to building your home. A systems approach focuses on constructing your home so that all parts function in an integral way that supplements, not hinders, each others performance. One of the leading proponents of this modern approach, Building Scientist, and educator Joseph Lstiburek, P. Eng. sums it up best when he says:
"The marketplace demands sophisticated, high performance buildings operated and maintained intelligently. As such, buildings must be treated as integrated systems that address health, safety, durability, comfort and affordability."
"Quality construction consists of more than good materials and more than good workmanship. If you do the wrong thing with good materials and good workmanship, it is still wrong. You must do the right thing with good materials and good workmanship…to promote the use of good materials and good workmanship in a systematic way, so that all the parts work together, promoting good performance, durability, comfort and health."
To accomplish this goal Lahr Construction Company is constantly examining how each building component integrates with all the others, in order to maximize overall efficiency and performance. For example: By installing high performance windows with a low U-Factor (the lower the U-factor, the greater a window’s resistance to heat flow and the better its insulating value), we are able to reduce solar heat gain throughout the house and that means that we can spend less on cooling equipment. The same types of savings, and increased performance can be achieved on the heating side through a little research and development. Instead of installing large oversized heating systems in your home our focus is to improve the overall tightness of the building envelope. Installing quality windows is just one example.
Q: What are some other areas that Lahr Construction upgrades beyond what is required by the local building codes or what is considered "industry standard?"
A: Below are some examples of the other areas of focus:
** Air Sealing Package:
We seal trouble spots were "hidden" air leakage can occur, like sill plates, window and door frames, heating and plumbing vents, electrical penetrations, and other areas. It is amazing how much small holes in the building envelope can translate to large percentages of heat loss from within the home.
"A 4 percent void area in R-19 insulation reduces performance 34 percent (the equivalent of a 50% increase in heat loss." – July 1979, INSULATION REPORTER – a study done by Johns Mansville Research and Development Center.
"Previous testing at Oakridge National Laboratory showed that low density (0.5 pounds per cubic food [lb./ft]) loose fill fiberglass suffers up to 50% loss of R – value at a very cold attic temperature (-18) due to air convection within the insulation" – May 1993, ENERGY DESIGN UPDATE
Through our insulation inspection process (by an independent and professional energy inspector) we can pinpoint these areas before they are covered up and seal them with inexpensive foams and sealants. The results of our own independent testing have proved positive as well. A final E-Star Rating on one of our recently completed 5-star homes demonstrates that our efforts to control air leakage will save our buyers over $145.00 per year in operating costs. – E-Star Test, Custom Residence, November, 2001
** Upgraded Insulation:
All of our homes feature upgraded Attic & Wall Insulation which saves you money! Not to mention a more comfortable home. With an average R-Value of 41.0 our Ceiling Insulation, for example, exceeds state code by 126%!! – E-Star Test, Custom Residence, October, 2000.
To achieve these kinds of results we recommend Blown-in Cellulose Insulation. It is safe, made of recycled materials, and provides superior insulation to fiberglass batts, which cannot be as densely packed inside wall cavities and around electrical outlets, mechanical & plumbing penetrations where air leakage occurs. For more information on cellulose insulation see The Cellulose Insulation Manufacturers Association (CIMA) @ www.cellulose.org
** Sound Framing Techniques using the latest products:
We pride ourselves on building a sound structure that can meet the demands of our Colorado Climate. In Colorado there are two major forces that can greatly affect the integrity of a wood framed superstructure: Wind loads, and snow loads (moisture can be another, although we do not experience as much rainfall as other parts of the country). Along the Front Range for example, it is not uncommon to experience winds in excess of 80 mph. To withstand the effects of these forces we engineer our homes carefully and specify the latest engineered building products to add additional strength to our structures.
Floors: For our floor systems we prefer manufactured TJI’s which can be easily designed to produce stiffer and more level floors than traditional milled lumber. In addition, a house constructed with TJI’s generally uses less lumber, and promotes conservation of our timber.
**Framed walls/ Window and Door Openings:
For tall walls with lengths up to 22 feet we prefer to use Timberstrand LSL studs. Timberstrand is a composite product manufactured by Weyerhauser Corp. that has several advantages over conventional wood products:
Every piece is covered by a product warranty against manufacturing defects for the life of the structure.
Uniformity and consistence of the product eliminates the problem of warping and cupping experienced with ordinary lumber.
Timberstrand exhibits great dimensional stability which results in stronger as well as straighter walls.
Long lengths of material (up to 22 feet or more) can be acquired meaning that our framers can build walls faster without splicing material. The end results are less waste, and strong, tall walls with fewer pieces and fewer joints.
We prefer using engineering LSL headers for our doors and window openings whenever possible. When we engineer a window header for example, we can use a single, solid beam across the width of the opening (rather than say three 2x10’s nailed together), which translates to less work (lower labor costs), and stronger, straighter openings. In addition we are again utilizing a product made of recycled wood fibers with reduces demand on our forests. In a remodeling situation, the use of engineered headers often allow for increased window header heights which can bring more natural light into a room. This is because as solid engineered beams, LSL’s are designed to be shorter than built-up conventional wood headers.
** Improved Air & Sound Quality:
As a member of the Built Green Program of Colorado, there are a number of things we do to promote health and safety within your home. The following upgrades are often standard feature in our Custom Homes:
1. Power-vented/draft induced domestic water heaters.
2. Sealed-combustion gas fireplaces with outside combustion air
3. Sealed-combustion, high efficiency forced air furnaces.
4. Sealed ductwork
5. Enclosed mechanical rooms, Insulated to a minimum of R-19 and sound proofed to STC 50+.
6. Only low-toxicity, solvent free adhesives used throughout construction. Standard is less than 150 grams/liter of VOCs. For example, our "Bostik Heavy Duty Sub-Floor and Construction Adhesive" from Prime Industries, Inc., Denver "is environmentally safer than solvent based adhesives and requires half as much product for bonding than solvent based construction adhesives." -Bostik, Product Specifications, Jan. 1988.
7. Paints and finishes that have minimal VOC content. Standard is less than 250 grams/liter of VOCs.
8. Ultra-quiet, "Panasonic" vent fans for bathrooms and shower areas. Our standard spec. is 0.5 to 1.5 sones, a normal ceiling vent fan typically runs at 3 to 4 sones (noisy) and uses considerably more electricity. One sone is about the level of noise produced by a new refrigerator.
9. Quiet, energy efficient appliances – such as the ASKO dishwasher with an encapsulated sound deadening tank.
10. Heat Recovery Ventilators for fresh air exchange. Modern, more air-tight homes "require ventilation to rid the dwelling of stale air, exhaust indoor toxins, and to protect the structure from the damaging effects of excess moisture….a controlled, well designed, ventilation system is a necessity." – The Green Builder’s Catalogue, Vol. 3, pg 1. For information on Green Building Products see www.positive-energy.com
11. Installation of Ceiling Fans
12. Beam Central Vacuum systems, which exhaust dust, bacteria, and pollens to a canister outside of your living area in the garage.
13. Radiant Floor/Hydronic heating systems, that can incorporate the environment friendly option of solar hot water (that option can save 50-70% of hot water costs based on E-star Energy Rating Reports.
14. Radon protection
