Hi,

I want to insulate my brick house and was talking with a company which drills holes in from the outside and injects foam.

Any advice?

Also looking to insulate my 3rd floor. Not much attic space for insulation to be blown in, no access points etc. The roof line is the ceiling on the third floor. It is a great space but cold in the winter and the ceiling gets very hot in the summer. House is from 1915. Is there a good solution?

Thanks

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Brick is commonly thought to insulate well, but actually it’s pretty bad. It has other good qualities though — moisture permeability, thermal mass, and it doesn’t rot nor need painting, etc.

The basic R-value of 1 is basically equivalent to one inch of solid wood, so for solid wood the value is 1 R per inch. Brick is much less at 0.2 R per inch.

Roughly (R/inch):

.2 Brick
1 Wood
3 Fiberglass or cellulose
4 compressed fiberglass
5 Styrene
7 polyisocyanurate
?? vacuum panels boast much more but are still way too expensive

So, with
1 inch of polyisocyanurate you can get the same effect as
7 inches of solid wood, or
35 inches of solid brick.

Most probably they pump polyisocyanurate in the gap between courses of brick, and double or triple the final R value of the brick wall by doing so.

R value is NOT the only important value though. If you insulate such that you don’t allow the moisture out, you can end up with rot or water-logged (and less-insulating) insulation.

Thermal mass will reduce heating and cooling in the spring and fall when there are 55 to 80 degree days/nights, but has much less benefit in the Summer and Winter.

Depending upon your house, lowering the thermostat for a few hours during the day may or may not save energy because the catch-up is less efficient. It is my untest opinion that the very massive houses typical of OTE, don’t benefit from daily thermostat setbacks, and in fact, it is possible in some situations that it may burn more fuel than leaving it at a constant setting. On the other end of the spectrum, low thermal-mass houses with little insulation can benefit from daily themostat set-backs though.

To cut down your energy bill, reducing air infiltration should be the first step. You can add R-50 everywhere and not notice much of a savings if your house is ‘loose’. Very often people insulate when actually they should be caulking, fixing windows, and sealing holes in the foundation and the top floor ceilings. After you have made your house tight, then focus on insulating.

Direct-vent furnaces and water heaters also help in that they don’t need to pull outside air in through your house for combustion, they pull and exhaust air directly through a dedicated vent.

Comments
Wed, 03/14/2007 – 16:05 — registereduser (not verified)
vapor barrier

what’s the best way to deal with a vapor barrier? Is primer a vapor barrier? What about Tyvek?
Wed, 03/14/2007 – 16:34 — Quint
Some primers are vapor

Some primers are vapor barriers, some are not, you have to check the individual products.

Generally, the best place for a vapor barrier is on the interior wall surface, i.e. the interior paint. Shellac, like BIN, is a good vapor barrier. Any moisture inside, will stop at the shellac and not travel outward and get your insulation wet, or cause rot. Regular interior wall paint is usually not a vapor barrier — the moisture goes through it.

If you are in an air conditioned home in a hot humid region, you will need the vapor barrier to be on the outside instead. Basically, you want to block the water vapor at the first surface. For most homes, the vapor inside, moving out, is usually the problem.

Tyvek is a plastic sheet that stops liquid water, but allows water vapor through. It is to prevent water from spashing, spraying, or blowing in. Is it similar to Gore-Tex but has a slower transmission rate. From a research project I did ten years ago, these are the numbers I recall. Tyvek breathes at about 35 milliliters per square yard per day. Gore-Tex breathes at 3000 milliliters per square yard per day. There were several types of tests for breathability too, so take this only as an illustration, not as hard data.

Quint

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1. Home Office Garage Conversion: How Much Insulation?

“I’m going to turn my garage into a home office. How much insulation should I use?”

~

A common mistake, when estimating energy costs, is to consider the square footage of a structure.

“If my house is 2000 square feet and costs $200 to heat in the middle of the winter, and my garage is 200 square feet, it should cost $20, right?”

This is roughly true in terms of heating them UP, but not for KEEPING THEM HEATED. Heat LOSS is a function of wall area.

Consider a 2000 square foot house and a 200 square foot garage. If they are both simple squares, the house is approximately 45 x 45 and the garage is 14 x 14. The total wall length for the house is 180 feet and the garage is 56. So the garage will cost approximately one-third to heat

House 2000 square feet
Garage 200 square feet

House walls are 45 feet long (square root of 2000)
Garage walls are 14 feet long (square root of 200)

Total wall length of House is 180 feet (4 times 45)
Total wall length of Garage is 56 feet (4 times 14)

Garage has 31% of the lineal wall footage of the house.

All things being equal, the energy cost to heat the garage should be 31% of the cost to heat the house, not 10% (based on square footage).

The bottom line is that smaller structures need more insulation.
HOW MUCH INSULATION?

So the next logical question is:

“If my house is insulated with R-15, what do I need to insulate the garage with to get the energy costs down to 10% of the house?”

I’ve read in many places that if you double your insulation, you cut your energy in half (inversely proportional). I’m not completely convinced of this, but it may be correct, so, in our example above, you’d have to insulate the garage with insulation of about R-45.

Other factors come quickly into view at this point.

AIR INFILTRATION — Allowing air to leak in or out can quickly undermine any attempt to reduce energy costs. Air leaks must be fixed first.

FRAMING — Wood framing does not insulate as well as actual insulating materials and dilutes the R-value of the wall. Top and bottom plates, window and door perimeters, jack studs, and cripples, even wiring and piping increase the conductivity of the wall.

ROOF and SOUTH-FACING WALL — This is a tough one. A black roof or south-facing wall can add a fair amount of energy to a structure during times of full sun. Ideally, the insulation could be ‘switched off” if the roof or wall were actually heating the home. Since that’s not possible, I’ve dreamed up a few systems to capture this heat, but haven’t built any yet.

WINDOWS and DOORS — usually have an R-value in the single digits. South-facing windows can let quite a bit of heat in during full sun.

GEOTHERMAL — If your house is build on dry sand, I don’t suspect you would lose much energy to the ground because sand is a poor conductor. On the other extreme, if you are on a marsh, you would continuously lose energy to the ground. The two factors are how conductive is the soil, and how much underground water movement is there.

Conclusion — Okay, so how much insulation?

I guess the bottom line is how much do you want to spend upfront, and how much do you want to spend in ongoing energy costs? If you want low energy costs, go with the high R-value in the wall (19 or 25), quality windows and doors, and a south-facing window with an awning for the summer. If you want to shave the upfront costs down as far as possible, put in minimal components and just heat the space during work hours with a programmable thermostat.

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1. R-value of Brick, Wood, Fiberglass, and other Materials

The purpose of caulking a tub or shower is to simply keep water from destroying your inner walls. This pliable and waterproof adhesive is applied to joints where walls, tub, and floor meet.

Begin by testing in several areas (particularly towards the bottom) for a loose or “spongy” wall. Caulking will not correct this condition. This wall must be replaced as water has leaked through the missing grout or caulk and deteriorated it. If unattended, the wall interior will become moldy. Protect the walls from further damage with an additional shower curtain if you wish to continue showering during repairs. (See “replacing a tub/shower wall.”)
Tools and materials you will need:

1. Caulking Gun. I like the dripless type. Caulk I use Polyseamseal, Tub and Tile.

2. Scraper This is a good detail scraper. It holds a disposable utility knife blade.

3. Grout saw Use this to clean the grout in between tiles.

4. Putty knife Use this to get into those nasty corners where other tools may not work.

5. Mini glass Scraper Use as a detail finisher only. This will hold the razor blade more securely in place.

6. Wallpaper scraper knife, 4″ This is my main caulk-removing tool. Using both hands makes the job easier and safer.

7. Broom Use to keep the tub clean. (a small plastic dust pan is helpful).

8. Non-Sanded Tile Grout Use to fill any voids between tiles.

9. Sanding sponge to remove any metal marks left by the knives, lime deposits, and to clean the grout between tiles.

10. Sponge to finish smoothing out the caulk.

Protective eyewear

Kneeling pad — to protect the tub, shower floor, and yourself.

Gloves — protection from sharp tools as well as chemical allergies.

Trouble light — showers are often dark.

Let’s get started.

1. Close the tub/shower drain to keep debris from falling into it.

2. Remove the old caulk with the wallpaper-stripping knife (see #6 on page 1 above)

Using both hands, cut close to horizontal then again close to perpendicular with several strokes until the old caulk is completely removed. Stubborn pieces can also be remove by using a gentle chopping motion with this knife.

3. Finish removing small pieces of caulk with the utility knife scraper (#2 above), the mini glass razor scraper (#5 above) and/or the sanding sponge (#9 above). Like all work, preparation is key to a clean profession job.

4. Apply caulk over clean and dry areas only. If you discover any water “bleeding” from any joint, stop and let this completely drain and dry (this could take overnight). Applying caulk over a wet joint will trap unwanted moisture and prevent the caulk from adhering to the joint and, further damage the wall.

Squeeze out only enough caulk to complete one line at a time. Caulk sets-up very quickly so, smooth it out with a “wet finger” as soon as you can followed by a damp sponge before proceeding to the next line. Work fast and try not to hesitate. You should end up with an even concaved line of caulk. Don’t worry. If you mess-up, simply remove the caulk and reapply.

It is unnecessary, wasteful, and more effortful to apply any more caulk than what is needed to fill the gap … remember, you are caulking not cake decorating. Check each line thoroughly before proceeding to the next … if you missed anything, merely add a dab more and use a wet finger to smooth it out.

Let the caulk dry over night before showering … it skins-over quickly but, it is still not cured.

5. Clean any mold (black stuff) from the tile grout by working the edge of the sanding sponge along the grout line. This is usually sufficient. If not, a light scraping with the grout saw will do the job. The sanding sponge will also remove lime deposits from the tile (you can also use vinegar, “Lime Away,” or “CLR.”).

6. Carefully inspect between each tile for missing grout. You must fill these voids before showering. Apply the unsanded premixed tile grout with your finger (or plastic spreader). Wipe off the excess with a damp sponge. Caution: don’t wait too long to wipe off the excess as it is difficult to remove when dry. The grout self cures in 2 days (keep dry by not showering or, install a protective curtain).

Keep your walls beautiful and mold free. Squeegee (good) then, sponge (better) or towel (best) your walls after showering. Gel-Gloss (liquid or spray) will keep your tile shinny and clean.

Ted Shalla Handyman

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The same thing is going on with the rainwater. It soaks right through the dirt, but can’t go past the clay. It flows along the contours of the clay substrate. So when people with wet basements slope their dirt away from their foundation it does little good. The water flows along the clay. When thinking about a wet basement you can ignore the topsoil and just think about the clay.

Often when homes are built, builders dig a trench, put in the foundation, then back-fill with anything around (stone, clay, dirt, whatever). This backfill is water-permeable. So, thinking only about the clay, you have a trench around your house. If the eaves drip down inside this trench the water will go right through the dirt, hit the clay, and flow towards your foundation. This is especially important when thinking about downspouts. You have to emit the water far enough away from the house so they are outside of the foundation trench.

What should be done to prevent this when building a new house?

1. Contour the clay substrate to slope away from the house.

For an excellent start, position the house on a rise. Take samples of the ground. If the topsoil is only a few inches deep and you don’t find any surprises (pits, old foundations, etc.), you can tell what the clay is doing.

2. Try to keep your trenching minimal.

Remember, for the most part, the contour of the undisturbed clay is the contour the rainwater is going to follow. If you can use trenchers instead of bulldozers, or only bulldoze from inside; and you can leave a nice sharp wall only a foot or so outside where the foundation will be you’ll be in good shape.

3. Design your eaves and downspouts to extend beyond your foundation trench.

You want the rainwater to fall far enough away, so when it hits the clay substrate, it flows AWAY from the house.

4. Lay in a perimeter drain.

Since you’ve designed a good clay substrate you should have very little water flowing towards your house and into your basement. But for added insurance, a perimeter drain is nice redundancy. I’ve seen several disagreements about what should cover your perimeter drain, and it depends upon how your clay substrate is layed out. I personally suspect that gravel, or ‘rip rap’ covered with gravel, covered with fine mesh is probably the best.

What can you do to fix it after-the-fact?

1. Check your downspouts.

Are your downspouts emitting the water far away from the foundation? Can you pipe the water away into a drain? This is usually the major contributor to wet basements.

2. Check your gutters.

Any chronically overflowing gutters might be contributing a lot of water to your basement troubles. Fix your gutters. Keep the leaves out so they don’t overflow. Fix the slope so they drain into the downspouts. If they are sagging in the middle, fix the supports. If they have holes, fix the holes or replace them.

3. Install perimeter drains.

This can be ridiculously expensive, or not too bad. It depends upon your conditions. But often just gutter and downspout repair can help dramatically.

4. Make your basement sea-worthy.

If you think of your basement as a boat, and you make it water tight, you can simply keep the water out that way. It’s a better idea to alleviate the source, but if the problem is not from gutter and downspout water, this is often the only affordable solution. Plug up the holes with cement, and paint the foundation with a product like Dri-Lock which stops the water from coming through. Seeping or leaking water does more damage than still water, and if the water is not coming through you won’t have the humidity and mold problems.

It’s a common problem.

Wet basements are very common. Building materials and practices have gotten better and better, but time and cost is still a factor in construction. If you consider how the clay is laid out, you can design a drier basement from the start, or have a good chance at fixing a wet basement.

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