Exterior Wall Insulation

[SaintCyr]

I'm attempting to make my home a little bit more efficient and have been looking at adding insulation to all the exterior walls. I have a 1920s bungalow thats block and beam wood framed structure. I have heard stories of this creating issues with moisture in the walls here in Houston or issues with "stopping" air flow through the walls and into the attic. Soooo, my question is what I can and cannot do in regards to insulating the walls. I have done this before with batts and have an easy method for getting them in the walls but it was in NW Arkansas where the humidity is a lot lower. Thoughts?

Thanks,

D

[barracuda]

I'm attempting to make my home a little bit more efficient and have been looking at adding insulation to all the exterior walls. I have a 1920s bungalow thats block and beam wood framed structure. I have heard stories of this creating issues with moisture in the walls here in Houston or issues with "stopping" air flow through the walls and into the attic. Soooo, my question is what I can and cannot do in regards to insulating the walls. I have done this before with batts and have an easy method for getting them in the walls but it was in NW Arkansas where the humidity is a lot lower. Thoughts?

Thanks,

D

If you want to keep the existing sheetrock, you can have foam insulation injected/spayed into the exterior walls from the inside. It's a messy (dusty) process and will result in small quarter-size holes in between each set of studs. You will have to sand them down and repaint them afterwards. There are some professional services that will do this for you. Some of the foam/cellulose insulations have built-in fungicides and protection against pests. Just look up insulation in the yellow pages (or pm me, I know someone who is relatively inexpensive). Get multiple estimates because the quotes can vary widely.

[SaintCyr]

If you want to keep the existing sheetrock, you can have foam insulation injected/spayed into the exterior walls from the inside. It's a messy (dusty) process and will result in small quarter-size holes in between each set of studs. You will have to sand them down and repaint them afterwards. There are some professional services that will do this for you. Some of the foam/cellulose insulations have built-in fungicides and protection against pests. Just look up insulation in the yellow pages (or pm me, I know someone who is relatively inexpensive). Get multiple estimates because the quotes can vary widely.

I'm looking at doing it from the outside without damaging the siding. We have done it in the past where we remove several pieces of the siding and gain access to the walls this way and installed batts. I'm just worried that it will create a moisture trap in walls or attic.

[BryanS]

I'm looking at doing it from the outside without damaging the siding. We have done it in the past where we remove several pieces of the siding and gain access to the walls this way and installed batts. I'm just worried that it will create a moisture trap in walls or attic.

Just do this exact same thing again. And don't worry about it.

[musicman]

I'm looking at doing it from the outside without damaging the siding. We have done it in the past where we remove several pieces of the siding and gain access to the walls this way and installed batts. I'm just worried that it will create a moisture trap in walls or attic.

so do you repair the water barrier that each house has on the outside, under the exterior material?

[rbarz]

What about fire stops?

[SaintCyr]

The houses we have done so far havent had a moisture barrier under the siding. The houses that have the fire stops we just find the location and pull the siding off there as well and do the same thing. So am I under the impression that there is no issue with creating a moisture barrier with adding insulation?

[RedScare]

I don't think you have anything to worry about as far as moisture barriers. I think what everyone is thinking of when they say 'moisture barrier' is actually a vapor barrier, such as Tyvek. Vapor barriers are most useful in preventing air flow through the wall, thus making the house more energy efficient. Obviously, installing insulation is better than nothing, even without a vapor barrier. As long as the wall is dry, you shouldn't encounter any problems.

[BryanS]

The houses we have done so far havent had a moisture barrier under the siding. The houses that have the fire stops we just find the location and pull the siding off there as well and do the same thing. So am I under the impression that there is no issue with creating a moisture barrier with adding insulation?

No. Just do exactly as in the picture.