Archive for the ‘insulation’ category

Furnace fan, to distribute heat throughout the house?

January 31st, 2013

Question:

I have a two-story house with a basement, built in 1952. Is it a good idea to turn the furnace fan on, to distribute the heat throughout the house?

– Marian

Answer:

H014 - Warm Air Furnace Fan and MotorYes and no. If you have a problem with a cool area when heating or a warm area when running the air conditioning, operating the fan continuously will even out the temperatures in your home. The downside is this will cost electrical energy to run the fan and cause some wear and tear on the fan. However, you can run a fan on a newer, high efficiency forced air furnace with an ECM or variable speed motor for little cost – about 1/10 the cost of a typical fan motor. Finally, I think your first step is to have a contractor inspect and adjust your system. At times, duct dampers can be adjusted to correct cold spots and air flow problems. Often you need to make a spring and fall damper adjustment for a two story home.

– Mr. Fix-It

Energy Efficiency Improvements – Where to Start?

August 21st, 2010

QUESTION

I have some funds to do energy efficiency improvements to my old (1950’s) home, but I don’t know where to start. The home is well maintained, but has had no energy improvements. It seems that every contractor has the best product, and there are many claims about huge energy savings. The government rebates and tax credits just seem to complicate the issue. Where do I start?

ANSWER

There is no simple answer. I can outline where to logically start, but I think your home deserves an evaluation and some scientific testing before you start spending.

I suggest you contact Focus on Energy. Their goal is to provide information, resources and financial incentives to help improve energy efficiency in Wisconsin. The state program is well known throughout the country.

I used the Focus on Energy program called “Wisconsin Energy Star Home Program” when I built a new home. They gave advice on construction details, and worked with the builder on energy efficiency. The results were fantastic.

For existing homes like yours, they offer a service to scientifically evaluate your home and the systems in your home at a very reasonable price. Their consultants can test for leaks, review your equipment, and use a computer model to identify the best areas to invest.

Overall, you should look at the easy energy improvements and your old equipment. If you have a furnace that is over 25 years old, put that at the top of the list. If the attic insulation has never been improved over the original three to six inches, that should be high on the list as well. Insulating the top of the basement wall, using low-flow plumbing fixtures, fluorescent lamps, and a set-back thermostat are simple changes with a great payback.

An evaluation by the Focus on Energy is the best first step. They also offer a new interactive website at Ask Focus on Energy. They will answer your questions and refer you to a large database of answers. If you have a unique question, one of the experts can respond.

Should I Install Sub-Floor Panels When Finishing a Basement?

March 25th, 2010

We are installing a rec-room in our basement. Some of the books I have read recommend installing sub-floor panels over the concrete floor in order to provide extra warmth and help prevent moisture. Is it worth the extra expense? If so, is there a brand you would recommend?

Answer:

ComfortBase from HomosoteWhen installing carpet or floor covering on a concrete basement floor, always try to add some type of insulation. The concrete slab is in contact with the damp soil. This will make the floor covering cool and subject to condensation, resulting in a musty, mildew smell. A little insulation will make a huge difference.

I suggest ComfortBase from Homosote. It is a 1/2-inch-thick resilient fiber-board that cushions hard concrete and provides a thermal break. The single-ply concrete flooring system is perfect for finishing basements or improving concrete slab floors, while also increasing the floor surface temperature. ComfortBase is easy to apply over concrete floors with adhesive, or floating the panels on the surface.

You can only build a rec-room if the basement is totally dry. It’s a great product but a little hard to find at times. Many home improvement folks don’t know about the it, so you can educate them.

Basement Finishing: Insulation and Obstacles

March 4th, 2010

I have a 1920s house with a dry, block basement. I’m thinking of insulating and finishing it, but hesitant about the ceiling. I have a high-efficiency furnace, but the old-style heat runs with foil-faced cardboard between the joists, serving as cold air returns. This area has a lot of other electrical and plumbing obstacles in the way.

I have found fire-rated faced batt insulation. Would it be legal to insulate my basement ceiling with it? Alternately, I’m thinking of just insulating with R-11 Kraft faced, and covering it with straight-edge ceiling tile (2″ x 4″) fastened directly to the joists.

Answer:

When finishing a basement there is little reason to insulate the ceiling, except to deaden sound transmission through the floor. The upper and lower level will be about the same temperature, so insulation is not needed between the floors.

You should however insulate outside walls. Pay particular attention to the area above the foundation wall to the floor framing. This is an area with a lot of potential for air leaks because of all the framing joints. The best insulation and sealing would be spray-foam from the top of the basement wall, over the sill plate, on the band joist, and to the subfloor. Check with your local code officials for their requirements.

I am not aware of any fire-resistant rated fiberglass. You can’t use a paper or Kraft faced fiberglass because the paper is flammable. Don’t insulate between the floors; it is a waste of materials and time.

Sealing Space Between Kitchen Cabinets

January 16th, 2010

Question:

My brother-in-law and I installed new kitchen cabinets last spring. Everything turned out great, except for one oversight. A few wall cabinets have dead space in between them, and they are open at the bottom. It’s allowing outside air to come through the bottom of the cabinets. What kind of insulation might you recommend to fill these cavities? Would fiberglass be safe to use?

Tony

Answer:

I assume you do not have solid drywall at the top of the cabinets to the attic and this is allowing air movement. You can seal the gap with anything that’s solid – drywall, wood, metal, or plastic. Fiberglass or insulation will not stop air movement.

You should also have a complete air seal from the heated space to the attic. In fact, you must have an air seal to prevent heat loss and moisture damage into the attic.

Tom

Insulating a Poured Wall Basement

January 13th, 2010

Question:

We are in the process of finishing off our poured wall basement. It will be 2×4 construction and is about 80% below grade. I plan to use R-13 unfaced fiberglass insulation. Is this the best choice to insulate and prevent moisture/mold issues?  My thought was that it will allow the walls to breath. Our home is about 6 years old.

Kevin

Answer:

When finishing a basement, you should check with the local building inspection department to understand what they require. In the state of WI, no vapor barrier is to be used when finishing a basement. This confirms your idea – if water ever enters the wall, it can evaporate to the heated space.

The best option is to set the studs an inch or so away from the wall, complete the wiring, then have a contractor spray foam insulation from the floor slab up to the sub-floor of the first floor. This seals any air gaps while providing excellent insulation and water resistance.

Tom

Leaky Bathroom Fan – Drip, Drip, Drip

December 30th, 2009

Question:

I have a bathroom exhaust fan that is vented into the attic, up to the ridge-vent area. Since the weather had gotten colder, water drips back into the bathroom from the fan after it has been on for a while. Do I need a certain type of material for the vent? Should I insulate it? I’m not sure what the solution is. Thanks for your help.

Glen

Answer:

Your problem is condensation in the cool fan duct. Warm, moist air from the bathroom condenses on the cool duct and runs down the duct to the fan. The duct is now cold because the attic is cold.

The duct should be insulated. Make as short of a run as possible to a vent connector through the roof deck. The fan duct should not be run to the ridge-vent. You can find insulated duct and a vent connectors at a building supply store.

The fan and the vent connector through the roof should also have a damper that closes when the fan is off to limit air movement.

Tom

More Insulation in the Attic?

December 21st, 2009

Question:

Where can I find someone who can tell me if I need more insulation in my attic?  I’m afraid that if I go to an insulation company they will say I do, when I really don’t.

-Ruth

Answer:

Insulation - Thermal Boundary/EnvelopeThe question should really be where can I make energy efficiency improvements that save me the most money. While insulating the attic is often high on the list, what about the furnace, basement sill plate, etc.?

I suggest you have a energy evaluation by a Focus on Energy Consultant (800-762-7077). The consultant will review, test your home, and establish a priority list for improvements. I think it’s a great deal.

As far as the attic, you need about 12 inches of insulation (about R-38). More is better, but may not always provide a payback. See my website article at the Free Articles page titled Insulate Your Attic – But Don’t Stop There. It will explain insulation and air sealing. The air sealing is more important than the insulation.

-Tom