{"id":382,"date":"2010-01-04T09:39:54","date_gmt":"2010-01-04T14:39:54","guid":{"rendered":"http:\/\/energyrealist.com\/?page_id=382"},"modified":"2010-01-04T09:39:54","modified_gmt":"2010-01-04T14:39:54","slug":"stick-built","status":"publish","type":"page","link":"https:\/\/energyrealist.com\/?page_id=382","title":{"rendered":"Stick-built"},"content":{"rendered":"

In the US 90%+ houses are built using the familiar system of studs (wooden 2×4 or 2×6 and their metal equivalents), with interior drywall and exterior sheathing, housewrap (Tyvek being the most common trade name) and siding.<\/p>\n

The method is familiar, cheap, flexible and easy to alter and maintain.\u00a0 The downside is that it is almost always leaky as a sieve.<\/p>\n

As energy conservation and air-tight housing has become a fashionable topic more and more material is available on how to build, and retrofit, stick built houses that are energy efficient.<\/p>\n

The Journal of Light Construction<\/a> (JLC) in the November 2009 edition has an article by David Joyce on “Retrofitting Exterior Insulation”.\u00a0 This is about an 80 year old house in a Boston suburb.<\/p>\n

I like JLC.\u00a0 Every issue seems to have at least one article that I find relevant and the style of writing and illustration are usually clear and with little bull-shit.<\/p>\n

The diagrams below show my summary of this retro-fit.\u00a0 The full article, with much better drawings (!), is at jlconline.com<\/a><\/p>\n

\"dwg<\/p>\n

Here’s the wall diagram.\u00a0 The article is worth reading for the detail on water planes and the treatment around windows and doors.\u00a0 R39 is not bad compared to the usual R20 or less.\u00a0 Plus staggering the seams in the insulation panels and taping them helps a lot in air sealing.<\/p>\n

\"dwg<\/p>\n

The roof – again a great improvement on the standard.\u00a0 The items marked with the * are my additions and not part of the original article.\u00a0 The idea is to add 2×3’s on flat running vertically and screwing the final roof sheathing on top of that.\u00a0 This provides an air channel below the roof shingles.\u00a0 The bottom of that channel needs to be sealed with insect screen, and the top with normal ridge venting.<\/p>\n

Of course there are multiple opinions on this subject.\u00a0 Is the extra cost worth it?\u00a0 The air gap provides the equivalent of a “tropical roof” reducing summer heat load to the house and also lengthens the life of the shingles.<\/p>\n

The January 2010 issue of Fine Homebuilding<\/a> has an article by Bruce Coldham on “Six proven ways to build energy-smart walls”.\u00a0 Bruce looks at:<\/p>\n