After 18 years of experience as a custom home builder in Routt County, plus lessons learned completing three extensive rebuilds for his own family, Eric Rabesa has some advice for home buyers about top construction decisions.
Working with a home builder or remodeling contractor can seem like an endless maze of choices, so Rabesa suggests home buyers spend more time and attention on 10 top concerns. He dubs the list “top 10 above-code no-brainers.”
ERV/HRV, or Energy Recovery or Heat Recovery Ventilation
Although locally adopted 2015 building codes require balanced ventilation, that can mean different options with different builders. Consider a full ERV or HRV system, and a mechanical contractor can help evaluate which to use based on how a family will live in the home.
“It is a small increase in cost for a far superior system that benefits the health of the home and its residents,” said Rabesa, owner of Rivertree Custom Builders.
Do not cut corners when it comes to a well-insulated thermal envelope. “A thermal envelope is very expensive to upgrade at a later date,” Rabesa said. “It lasts the lifetime of the home, and the home lives more comfortably with lower utility bills.”
Spend time with your construction professional to evaluate the options. “With the new energy codes, the flexibility is there to insulate walls with multiple assemblies,” the builder noted. “You may be surprised what an incremental cost increase can yield in energy efficiency.”
Each home should be considered on a case-by-case basis, but Rivertree often combines insulated Zip panels that provide continuous insulation with spray foam inside the wall cavity to prevent condensation and create an excellent air barrier. The remaining wall cavity is filled with BIBS, or a blown-in blanket system, for a wall assembly with more than an R-30 value.
Foundation perimeter insulation
Consider an upgrade to three inches of closed-cell rigid foam insulation instead of the required two inches. Homeowners may find that the cost for the thicker material is warranted when considering its impact to the overall wall assembly insulation rating.
Rabesa is a fan of full under slab insulation with a reflective radiant heat coating such as the Amvic “egg crate” system that has multiple benefits. In addition to energy efficiency, some of the Amvic systems work as a vapor and air barrier for radon mitigation as well as eliminating the need for a wire mesh mat to tie in hydronic heat tubing.
Blowing additional loose fill insulation into an attic “is really a no brainer,” Rabesa said. Although current code minimum is R-49, he suggests asking insulators to blow R-60 as long as there is still room for proper venting for the preferred cold attic design.
Upgraded window glazing
While windows are desirable for natural lighting and fresh air, they represent holes of heat loss in an otherwise well-insulated building shell. Rabesa suggests buying the best windows the budget can bear. That doesn’t necessarily have to mean triple-pane argon-filled windows, but at least compare several top-quality window brands. First become well-versed on the five window factors to be a smart shopper: U-Factor, Solar Heat Gain Coefficient, Visible Transmittance, Air Leakage and Condensation Resistance.
Blower-door test during insulation stage
Even well-built homes with great subcontractors have a few tucked away places where insulation and air sealing can be missed. Ask the builder or local energy auditor to perform a blower-door test with infrared imaging before drywall is installed when air leaks can still be fixed. Schedule the testing while the appropriate vendor is still on site so that issues can be fixed via blower-door guided air sealing. Watch for common areas of missed or insufficient insulation such as behind pipes, under bathtubs, wiring and plumbing penetrations, and angles where ceilings meet exterior walls. Missed insulation patches in attics, for example, can lead to rising heat from the home causing ice dams on the roof and condensation problems on ceilings.
“Even the best construction guys need to be checked because nobody is perfect and houses are complex. It doesn’t take much to lose that energy efficiency you are working so hard to achieve,” said Rabesa, who recently discovered an uninsulated corner in his home’s master bedroom ceiling. “It looked perfect, but once I turned on the blower door, I was able to detect air making its way in.”
Under tile waterproofing membrane system
A leak under a bathroom floor can mean mold, possible structural damage and expensive repairs. Ask the builder to install a tile underlayment system made by such companies as Schulter or Laticrete. The flexible, waterproof membrane systems are intended to prevent cracking of tile and grout and to protect moisture-sensitive subflooring. If the system is used correctly, both companies offer significant warranties.
Prewire for possible future solar installation
For his most recent home remodel, Rabesa, a University of Colorado environmental science graduate, asked a local solar installer for a consultation. Prewiring for future solar electricity and making sure the electrical breaker box is sufficiently sized is much cheaper during initial construction.
Set final grade and lay gravel under decks
Home construction often begins when the final grade is complete under only the home’s footprint. Ask that the final grade also be completed under any forthcoming decks or porches. That way water will drain away from the house properly and gravel under tight spaces can be spread efficiently.
“It’s really common when I do a remodel to find the exterior grade sloping back toward the house, or over time the homeowner has added plantings or beds that did not account for proper drainage,” Rabesa said.
No doubt, building a home or undertaking a major remodel is a big investment, so be prepared to spend the necessary time to work with the builder to discuss key priorities that matter to the life and energy efficiency of the home.