Old brick house and little money… what’s the solution?
I am friends with two guys, whose old and stylish Pittsburgh house is really drafty. There is no doubt in our minds that this is not good for the environment… nor their comfort. Last month the bill was $500, and with the thermostat kept relatively low. The house is ~1,800 sf, 2 story.
The challenge is the cost of expected wall treatment in light of moving out in ~2-3 years. The interior walls have excellent looking wood half-panels that are part of house decor – impossible to think of covering them… We also heard of people who, against advice, blew some insulation into the gap between the brick and basically ruined their wall due to moisture condensation.
Would you give us some ideas of what you think is possible in this situation?
Here is more details from my friend’s email:
My attic insulation was the easy part, I have 18 inches of fiberglass insulation in the attic. The wall construction is exterior brick a small 1 to 1.5 inch air gap, interior brick and plaster placed directly on the interior brick. There are pockets in the interior brick to hold the floor joists. In my kitchen I have insulated an exterior wall with rigid foam insulation then built a 2×4 studded wall and insulated between the studs with fiberglass insulation. I have homemade storm windows on the interior of my windows which help control drafts and heat loss. I have not had an energy audit, I feel that I know where the flaws are in this structure. The biggest obstacle is that given my neighborhood and the low cost of housing I will have a difficult time recovering any improvements I make. I am however always interested in learning anything new so thanks for the offer and I will be glad to hear any suggestions.
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Replies
Lucyna,
The most likely avenue for savings in this house would be air sealing. Check with your local utilities or state energy office to find out whether subsidized energy audits are available in your area. Depending on your friends' income, they may qualify for free weatherization from the Weatherization Assistance Program.
One way or another, you need a blower door test. The blower door test will reveal the best opportunities for air sealing -- usually on the attic floor and in the basement.
And in evaluating the cost effectiveness / payback of improvements think of the money / time you invest in your own pleasure and happiness. Put some value on making your home more comfortable.
P.S. I second the suggestion of the blower door audit -- the lack of wall insulation is probably not the root of the problem, but rather air movement inside the walls are turning the attic insulation into an expensive filter as the air moves through it and out the attic vents. The blower door will both find the problems and let you know if the improvements you've invested in actually work.
Go Steelers!
building science tells us to go after air leaks then insulate. maybe invest in an ERV or HRV - not too expensive if you can do the ductwork yourself. I have heard that insulating inside a brick wall moves the freeze/thaw cycle into the brick and it destroys the brick.
It may accelerate freeze-thaw and other moisture-induced damage to the brick, depending on conditions.
It certainly will change the thermal gradient through the brick wall, bringing outside ambient temperatures - both cold and hot - deeper into the facade. And, by reducing thermal flux through the brick, it will also change the moisture gradient, reducing drying rates to the outside in winter and to the inside in summer.
If the cavity insulation is a vapor barrier, such as closed-cell foam, then there will be no drying to the interior when sun-driven moisture transport would have previously dried the brick and mortar. Increased moisture loads can increase freezing damage as well as efflorescence and osmotic spalling.