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jeanjess
Will adding insulation to the attic keep my house cooler
jeanjess

I live in an old home that is like a sauna on the 2nd floor. I have two bedrooms that I can't afford to get AC units in. I was told by an energy inspector that insulation should help. I can't afford insulating my whole house with blown in insulation. I have a big attic. Will adding insulation bats to my attic floor help keep the attic heat from penetrating the rooms? I have tons of batt insulation lying around that i could layer on the attic floor?

A. Spruce
Re: Will adding insulation to the attic keep my house cooler
A. Spruce

A good thick layer of insulation is always a good idea in an attic. Standard has always been R-30, though in recent years a second layer of insulation has become more popular. The first layer should be between the ceiling joists, the second layer runs perpendicular. Be careful to leave space around light fixtures, motors, and other electrical appliances so that you don't create a fire hazard, unless said fixtures are rated "I.C.", which means "in contact" with insulation.

brewster
Re: Will adding insulation to the attic keep my house cooler
brewster

Build a "survival room"/ a "retreat from the heat".

One strategy used by many homeowners to comfortably survive the hot summer days is to designate a single room (bedroom/living room/den, etc.) that can be shut off from the rest of the house by one or two doors where the whole family CAN RETREAT TO on those hot summer days & nites to escape the worst periods of heat-----spend all your limited funds on insulating that single room in the walls, floor & ceiling & make sure there is a double-pane window(s) to keep the heat out---add an AC for full comfort.

Many houses have a sub-grade cellar/utility room that is an excellent choice to modify into a below-grade "summer retreat" for this purpose---very little summer heat radiates down to such a cellar & whatever does can be eliminated with a small AC.

Given the short period of "dog days" in most parts of the country that soon end with the fall weather, having TV & other entertainment in the "retreat room" will allow the family to survive the summer heat & the summer will soon be over---there will always be several days & nites in July/August when the whole family will have to stay in the "survival room" to beat the heat.

What general part of the country do you live, & are the "dog days" confined to mostly July & August????---this strategy can be followed until funds are available for a whole-house insulation/AC project, or you decide to move elsewhere---how large is the family????

Have you gotten estimates for how much it will cost to properly insulate & install AC for the entire house????

jeanjess
Re: Will adding insulation to the attic keep my house cooler
jeanjess
brewster wrote:

Build a "survival room"/ a "retreat from the heat".

One strategy used by many homeowners to comfortably survive the hot summer days is to designate a single room (bedroom/living room/den, etc.) that can be shut off from the rest of the house by one or two doors where the whole family CAN RETREAT TO on those hot summer days & nites to escape the worst periods of heat-----spend all your limited funds on insulating that single room in the walls, floor & ceiling & make sure there is a double-pane window(s) to keep the heat out---add an AC for full comfort.

Many houses have a sub-grade cellar/utility room that is an excellent choice to modify into a below-grade "summer retreat" for this purpose---very little summer heat radiates down to such a cellar & whatever does can be eliminated with a small AC.

Given the short period of "dog days" in most parts of the country that soon end with the fall weather, having TV & other entertainment in the "retreat room" will allow the family to survive the summer heat & the summer will soon be over---there will always be several days & nites in July/August when the whole family will have to stay in the "survival room" to beat the heat.

What general part of the country do you live, & are the "dog days" confined to mostly July & August????---this strategy can be followed until funds are available for a whole-house insulation/AC project, or you decide to move elsewhere---how large is the family????

Have you gotten estimates for how much it will cost to properly insulate & install AC for the entire house????

It's about 15K to blow in insulation in my house. Add another 30K for AC and another 50K for windows. You can see my dilemma :)

jeanjess
Re: Will adding insulation to the attic keep my house cooler
jeanjess
A. Spruce wrote:

A good thick layer of insulation is always a good idea in an attic. Standard has always been R-30, though in recent years a second layer of insulation has become more popular. The first layer should be between the ceiling joists, the second layer runs perpendicular. Be careful to leave space around light fixtures, motors, and other electrical appliances so that you don't create a fire hazard, unless said fixtures are rated "I.C.", which means "in contact" with insulation.

When you say ceiling joists do you mean in the roof? I think I will go ahead and then try putting the insulation I have leftover from other projects - several rolls on the attic floor. Sounds like it may help a little. Thank you

A. Spruce
Re: Will adding insulation to the attic keep my house cooler
A. Spruce

Imagine a simple drawing of a single story house, you have a square for the living space and a triangle for the roof/attic. The ceiling joist would be the bottom of the triangle, it is the framing member that the ceiling below is attached to.

So, is this a finished attic? you say lay more insulation over the floor, is there actually a floor?

Sombreuil_mongrel
Re: Will adding insulation to the attic keep my house cooler
Sombreuil_mongrel

Insulation in the second floor ceiling will help, but installing some form of forced attic ventilation is cheaper. A whole-house fan will allow you to draw cooler evening and night air through the house, and the change of air and moving air makes a big comfort difference.
In the summer I put up screens in my 3 attic windows and a 1500 CFM fan sits in front of the south-facing window blowing outwards, which draws air in through the other two windows, or sets up a draft through the living spaces if I keep the attic door open. A walk-up attic has its advantages.

ordjen
Re: Will adding insulation to the attic keep my house cooler
ordjen

Attic insulation, especially where none is present, makes a dramatic difference. My present house had no insulation over the attached garage ceiling. As I use this space as my workshop, it was very hot out there in summer. I simply rolled out insulation between the rafters. The more the better , but even a few inches will help. My garage is also heated in winter, so the payback in terms of money and comfort is doubled.

My garage was drywalled and finished by the builder, but had no insulation in the outside walls either. As Portland, Oregon is relatively mild in winter, I have not bothered to try to retrofit the walls, especially since two of the walls are party walls to the house.

As Sombreuil points out, ventilation in that overhead attic space is also very important. Ideally, you would want that attic space to be no warmer than the ambient outside air. Plenty of eave vents and roof vents high on the ridge line of the roof will create natural convection air currents and help take the heat load off your bedrooms below. Of course, ventilation is also going to make it colder in the attic in winter too, so insulation is also important to keep the bedrooms warm in winter and your fuel bill down. It is a win/win summer and winter!

Mastercarpentry
Re: Will adding insulation to the attic keep my house cooler
Mastercarpentry

Keep in mind that of the left-over insulation is faced, you'll want to peel the facing off before laying it to avoid moisture becoming trapped in the insulation. You almost can't over-do attic insulation but you also need adequate ventilation to go with it- it's a system as much as the individual parts and best results only happen if it all works well together.

Phil

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