Aerobarrier existing homes
I have a large 1974 existing home that we purchased a few years back and am considering doing an aerobarrier seal on it.
Home has basement, main floor, 2nd floor. All bedrooms are on 2nd floor.
Home has AC and forced air heat.
Currently home tests at 4.9 ACH.
Walls are 2 x 4 with batt insulation and brick veneer.
Live in an area where radon is a concern.
Considering doing a ERV unit – when I talked to some of the local HVAC contractors they didn’t even know what it was- this should alleviate the radon concern and provide fresh air intake to make up for the no longer drafty home.
Thoughts on this? How tight could I seal the home if I do the ERV unit?
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Replies
I will type a response to give your post a boost. From my own research on Aerobarrier, there seems to be quite a range on pricing. Some of this is probably due to the company's franchise business model. But degree of treatment (and whether dealing with new or existing structures) also affects price. You pay more to reduce air leakage to Passive House levels, for example.
How far should you go? A lot will depend on your budget and whether or not you care about return on investment.
The cost of the aerobarrier is less of a concern to me as we plan to keep the house for quite a while and our heat gets kicked up quite a bit in the winter in the rooms that are "less comfortable." They said bringing it down to 3 ACH vs 1 ACH won't make a cost difference to them, however to go below 3 they require ventilation to meet the needs of the building. Hence the ERV.
Resinarch,
My only concern would be the at 4.9 ach you may have several gaps larger than can be filled by aero-barrier. it might be worth spending a bit of time doing the rough air-sealing before getting aero-barrier in.
If cost is a secondary issue, I would get the house as tight as possible and install a high-quality, balanced ventilation system such as Zehnder.
4.9 in a 1974 house seems exceptionally good (though this could be a more relaxed standard than Europe uses?). Has someone done a lot of stuff to seal it up already?