Published on March 18th, 2016 | by Henri0
Builder omits house wrap under siding
Q. Our house was built about seven years ago. During a recent repair to our siding, we found that the house had no building wrap (Tyvek) under the siding. This explains why the house does not retain heat.
It seems that we have two options. One would be to remove the siding, wrap the house, and then reside it. The second would be to blow insulation into the walls. What do you suggest that we do? Do you think that there are any other options?
A. I doubt very much that a house built seven years ago has no insulation in the walls, unless the builder was so irresponsible to not have done so. So blowing new insulation should not be an option.
You mention the absence of Tyvek, but is there another type of housewrap, such as felt paper, which was in common use until synthetic housewraps came on the scene?
The absence of Tyvek should not affect negatively the heat retention of your house, unless the house was built with strip sheathing, and there are gaps between the boards that let cold air in when the wind blows. That is also unlikely, unless the builder built it like a chicken coop (I have seen that before too.)
More than likely the house is sheathed with particle board or plywood and is, therefore, less subject to air infiltration – if the sheathing was applied properly. As you can see, there are a lot of “ifs and buts.” Without knowing more, it is difficult for me to determine why your house is not retaining heat as you put it.
You didn’t say, but I will assume that your siding is vinyl. If so, either felt paper or one of the housewraps on the market should have been installed under the siding, as specified by the vinyl siding industry. It is a serious error on the part of the builder to omit it. Your builder should remove the siding, staple a housewrap on the sheathing and put the siding back; this is not a cost you should have to bear, and, unless he or she is cooperative, you may need to take legal action.
If you opt for removing the siding to install housewrap, this is your last chance to increase the efficiency and comfort of your house by having 1-inch thick extruded polystyrene rigid insulation (XPS) or polyiso applied over the sheathing before putting the siding back. Any brand of synthetic housewrap should be placed under the rigid insulation.
As for the difficulty in keeping heat in, I’d look at the type of windows and/or their installation. Poor-quality windows and improper installation can account for huge heat losses.
I remember a case where clients had bought an expensive house, touted for the quality of the building process, that had such poor windows that the inside curtains would literally blow in the wind.by