DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Insulation and Radiant Barriers (
-   -   insulation floors and ceilings? (

bryce 09-07-2012 02:05 PM

insulation floors and ceilings?
As you may recall i am renovated a 1.5 story house soon.
I am confused about insulation
1) The basement ceiling. What i gather 6" of lose insulation is a good idea. I am thinking it is a problem to cover pipes and electrical work? Maybe cover it with small pieces that just cover each joicey space so they can be taken off in the future.
I heard you should caulk under neath there as much as possible or does it matter? Would a layer of Styrofoam board be simpler?
2) The ceiling on the main floor (the floor in the attic) People keep telling me not both insulating this but it seem like a good idea since i will spend most of my time on the main floor so why lose the heat to upstairs. Also i am not so sure how insulated the roof is.

So how much a difference will it be insulating the basement and ceilings?

nealtw 09-07-2012 04:51 PM

Insulating the outside wall will be more effective in the basement and then the plumbing won't be out in the cold. But all holes in the floor for plumbing and wireing should be made air tight for fire protection. I wouldn't worry about insulation to the upstairs accept for sound proofing. The main thing you want in the attic is good ventulation, air flow from the soffets near the gutters to the vents on one side of the roof near the top.

Perry525 09-10-2012 11:23 AM

1/ basement ceiling, do you want to keep the
basement warm?
Is there any heat down there?

Do you want to stop the heat from upstairs moving
down through the floor into the basement and being wasted?

2/ the main floor ceiling.
It is very important that you insulate this ceiling to
the highest standard, this is where most of your expensive heat is going.

3/ insulating the roof is a waste of time and money!
It should only be insulated if you are living up there!

I don't know where your house is, so this is generic
based on the coldest places.

Pull down the ceiling drywall, and fit as much sheet
polystyrene between the joists as you can, making
sure it is a tight fit, use cans of foam to fill any
small gaps and holes.

Fit three inches of polystyrene sheet tight butted
below the joists, fit new drywall below to protect it.

You (and everyone else) loose most of your heat
through the ceiling, it moves through holes and
cracks and through the drywall and the joists

Polystyrene is a closed cell sheet insulation that is
airtight, its made of thousands of tiny air bubbles
each covered in a thin plastic skin, each bubble
holds trapped air, that cannot move. The heat
doesn't pass through like solid wood. steel or
fiberglass or cellulose.

Polystyrene can be wet, covered in ice and it still
works keeping your home warm.

bryce 09-10-2012 11:41 AM

"2/ the main floor ceiling.
It is very important that you insulate this ceiling to
the highest standard, this is where most of your expensive heat is going."

Thanks Perry, that is exactly what i have been thinking, but everyone tells that it not necessary. The contractors, even the re agent.
Actually i got a good deal on Roxal insulation i just have to pick it up. It is 4"x3"x6' remnant strips.

Yes about the basement, the furnace will be down there, laundry. But i don't plan on much use of the basement. I think the insulation will prevent the heat from dropping down from the first floor.
Here's the room if you didn't see the other thread:
I don't think there is any insulation in the walls either. You can see the stairwell will lose lots of heat anyways.

Perry525 09-11-2012 03:31 AM

That photo tells a good story.
That stairwell will loose a lot of heat upstairs, it needs to be boxed in either at the bottom (preferably) or the top. As you walk up stairs, I am sure you can feel the heat as your face arrives at ceiling level. Not good.

Is that your front door? Is there an enclosed porch on the other side? If not, every time you open the door most of your heat will escape into the sky.
That probably should be your starting point, unless you can keep it closed all winter. Merely adding another door a few inches out, or in will make a big difference.

I suggest you buy an infrared temperature gun, you can get them on Amazon for about $20, these are wonderful, you point them at something, press the trigger and it tells you the surface temperature, you can then see at a glance how cold a wall, ceiling, roof, whatever is.

bryce 09-11-2012 12:06 PM

Sorry what do you mean by boxed in?
You still agree that putting insulation in the ceiling is good idea?

Perry525 09-12-2012 01:19 PM

Going back to that basement.
A furnace in the basement is a mixed blessing, it can help to keep the basement warm, yet if it doesn't have a dedicated make up air supply pipe it can pull cold air from the outside. And this can in turn mean cold floors upstairs.

Yes, insulating the living room ceiling is most important, loosing heat through the ceiling (and walls) as the air moves by convection, is the biggest loss and it leads to a cold floor.

Insulating the ceiling means that your furnace doesn't have to work so hard and the falling warm air is warmer and this keeps the floor warmer.

What I mean by boxing in the stairwell, is that you need a glass box and door either at the bottom of the stairs or at the top. This, like insulating the ceiling will keep the heat downstairs, leaving the bedrooms cooler and the living room warmer.

As the stairs are an important feature, while boxing in the bottom will save more heat, it is probably more practical and visually more pleasing to enclose the upstairs. Use glass or clear plastic sheet.

bryce 09-12-2012 01:34 PM

"What I mean by boxing in the stairwell, is that you need a glass box and door either at the bottom of the stairs or at the top."

You can't be serious? That would be seriously ugly. You make it sound like the north pole up there. I do appreciate insulation the ceiling feedback not sure i can see this one. You mean maybe a cover, are these 1.5 stories so cold?

You can see the attraction of this room is the open center space. I have feeling that whole pillar is going to need work.

All times are GMT -6. The time now is 04:48 AM.