Teandrie’s Iowa home needs new siding after sustaining damage in a storm, presenting him with an opportunity to add a layer of continuous insulation on the exterior of the house.
“I am considering going with an R-5 foil-faced insulation under the siding from Johns Manville,” he writes in this recent Q&A post. “It will cost me about $3000 to add the insulation, and I’m trying to figure out if it is worth that investment.”
The 2004 house, located in climate zone 5, has 2×6 walls insulated with batts. The plan is to leave the housewrap that’s already there, then add the 3/4-in. layer of insulation, and another layer of Tyvek to seal the building. He’s also planning to install new windows, upgrade the attic insulation from R-28 to R-60, and air-seal around recessed lights below the attic.
Teandrie says the contractor has balked at adding thicker exterior insulation because he thinks it will be too difficult to work around exterior electrical outlets. Teandrie also is concerned about two outdoor hose bibs, which have been spray foamed into place and are now immovable.
“Any thoughts or suggestions you have would be welcome,” he adds, and that’s where this Q&A Spotlight begins.
Outlet issue is an easy fix
The contractor’s concerns about exterior outlets is a pretty easy fix, says Kyle Bentley. There are many different types of weatherproof receptacle extensions that can compensate for the insulation layer, he writes, including one he found at Lowe’s. Or, says Zephyr7, put a cover plate with a knockout over the original box, then install a new box in front. This would accommodate the added thickness of insulation while leaving the original box accessible to satisfy code.
Likewise, there are simple solutions to refitting the outside faucets. Replace…
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