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tambone1972
No insulation in walls
tambone1972

I have a 3 story townhouse, the bottom level is extremely cold, the second level is moderately cold and the top level is warm and toasty. Actually top level gets too hot in winter as the thermostat is constantly being triggered by the colder downstairs. This townhouse is also an end unit so it takes the brunt of the cold. I recently realized that there is no insulation in the walls! I am planning on cutting square shaped holes in the drywall, between each stud, near the ceiling and blowing in the insulation, then patching them up.

My question is that since the top level is already warm enough, can I put insulation in the bottom levels only? Will it still work to provide a warmer environment downstairs, even though third story walls are not insulated?
Thanks
Tammy

brewster
Re: No insulation in walls
brewster

Tammy,

I would strongly recommend that you not attempt this yourself until you have first gotten 1 or 2 free estimates & price quotes from local INSULATION CONTRACTORS in your area, for several reasons:

1) you would have to cut A LOT OF SQUARE HOLES in the sheetrock/wall covering if you attempt to try this even on just the 1st floor, creating a lot of extra work for yourself/helpers (if any); then you would have to go back to reseal the square holes & repaint, etc. & you probably won't be able to get the wall appearance back to an acceptable condition.

2) The way this job is done by the pros is from the outside of the house, where the insulation contractor & helper removes a small piece of siding, clapboard, vinyl strip, etc. & BLOWS IN the needed insulation from a special truck that is designed for this job.

3) As part of the free estimate, before the contractor begins the job he/she inspects interior & exterior WALL CONSTRUCTION of the house to determine if there are any horizontal FIRE STOPS & other horizontal wood framing members inside the exterior wall to determine whether they would have to do one story at a time---in some framing constructions, they can start at the top outside of the house, remove a small piece of exterior siding, cut a small 3" hole in the exterior wood sheathing near the top of the house & blow in insulation from the 3rd floor that will also reach down to the 2nd & 1st floors---this is obviously the quickest & best way to do exterior wall insulation; the insulation contractors also have small ultrasound tools that can scan the exterior walls from inside & out before they do any wall cutting/hole-punching to determine the frame construction & vertical & horizontal stud (usually wood 2" X 4") locations so they can determine the most expedient & least costly way of making small holes to blow in the insulation.

4) I think you'll be pleasantly surprised at the cost estimates the insulation contractors give you--you can ask for a quote for them just doing the 1st floor & see if this solves the problem of getting adequate heat (and cooling in the summer) in there, then deciding if you want to do the upper floors at a later time.

5) I congratulate you on having the presence of mind to consider exterior wall insulation---this has to be one of the best ways to spend your limited "house expenses" dollars---you really can't lose when you have this done; the house is warmer in the winter, cooler in the summer, & you SAVE LOTS OF MONEY in the ensuing years on reduced heating bills & air conditioning bills --- You'll love it!

6) Do your research before you hire anyone:

Consult the Yellow Pages of the phone book under "Insulation Contractors" to get a list of ICs in your area; also use the internet to Google "Best residential house insulation contractors in (your city, state)" ---this search will usually trigger the internet to find various free polls & responses from homeowner's in your area who have recently had this job done, and have rated the contractor that did the job from excellent to poor on their performance & cost; if you belong to Angie's List, or other contractor-rating service (or know somebody who does), by all means also use this resource to try & find several high-rated ICs who have recently done a good job at a reasonable price in your area.

tambone1972
Re: No insulation in walls
tambone1972

Thanks for the info. I agree that it would be difficult to get the sheetrock back up to standards afterwards.

I have done some more research and read an article stating that brick homes insulated from the inside, can cause damage. As the warm air is no longer passing through walls, and causes freeze/thaw issues in the bricks.

Is that true?

If so perhaps that is why I have no insulation.
Thanks
Tammy

Dobbs
Re: No insulation in walls
Dobbs

Tammy:

This is another very good reason to get at least 1 or 2 free estimates from local insulation contractors---they will be the first to tell you beforehand whether your exterior wall cavities should have blown-in insulation in view of the brick exterior, or if there has to be some preliminary sealing step that has to be done to prevent moisture problems.

keith3267
Re: No insulation in walls
keith3267

But to answer your question, if you insulate only the first two floors, then they will not trigger the heat on as much and the third floor will not be so warm. Its probably best to do all three floors and turn off some of the dampers in the heating ducts to the third floor.

ed21
Re: No insulation in walls
ed21

Besides insulation it sounds like the HVAC needs to be balanced. If no dampers are present, they can be retrofitted.

tambone1972
Re: No insulation in walls
tambone1972
keith3267 wrote:

But to answer your question, if you insulate only the first two floors, then they will not trigger the heat on as much and the third floor will not be so warm. Its probably best to do all three floors and turn off some of the dampers in the heating ducts to the third floor.

All the upstairs dampers are shut already. Thank you for your reply.

keith3267
Re: No insulation in walls
keith3267
tambone1972 wrote:

Thanks for the info. I agree that it would be difficult to get the sheetrock back up to standards afterwards.

I have done some more research and read an article stating that brick homes insulated from the inside, can cause damage. As the warm air is no longer passing through walls, and causes freeze/thaw issues in the bricks.

Is that true?

If so perhaps that is why I have no insulation.
Thanks
Tammy

If you blow in insulation, it could be a problem for the brick. The freeze/thaw cycles will only be a problem if the moisture content in the brick is high. If the moisture content is low, then the damage caused by the expansion of water as it freezes should be minimal. There are many brick houses with insulation in the wall cavities that do not have any issues.

You need ventilation behind the bricks. You didn't mention the age of your townhouse so I don't know the type of construction used but if it is a typical framed construction with a brick facade (veneer, one brick thick), then there should be some type of boards on the out side of your framing and a small gap between those boards and the bricks. You should find a vertical gap in the mortar between the bricks near the foundation level every couple of feet. These are weep holes that allow any condensate water to run out and allow fresh air into the cavity.

There also should be some kind of opening at the top of the bricks, usually hidden under the soffit or fascia boards. Fresh cold dry air enters through the weep holes, is warmed up by heat escaping through the walls which dries the air even further, that is lowering its relative humidity, and makes it rise. As it rises, it will absorb any moisture from the walls and the bricks and exit out the top.

If you insulate properly, you need to add a vapor barrier to keep the moisture in the air in your house inside your house. Some heat will still migrate to the outside by conduction and radiation, but with the convection reduced by the vapor barrier, the moisture stays inside. Now your insulation will stay drier as well as the bricks.

If you blow in the insulation, you don't get the vapor barrier. But, there are some vapor barrier primer paints you can paint your walls with that will do pretty good job. Then you can use any type of paint you want as a finish coat. Vinyl wallpaper also makes a good vapor barrier.

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