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ashory 08-24-2011 01:01 PM

Insulating unfinished basement, First time home owner please help!
I purchased my first home in March and ripped ALL the carpet on the first level out. I realised afterward that even though the carpet smelt bad it was actually helping keep the living areas warmer. So now as winter gets closer I am starting to freak out about how cold it will get in the dead of winter not to mention what my heating bill will be. :eek: I moved from Sydney, Aus to Buffalo, NY so am particularly sensitive to the cold.

My Husband and I have been arguing back and forth he wants to recarpet but we were lucky enough when we pulled up the carpet to get decent looking wood floors and I would like to keep them.

So I was thinking we could insulate the basement. Now my basement is damp, not wet, just damp enough to smell bad. I had a waterproofer come over yesterday and he says it wasn't bad and could wait longer before I HAD to do something and I just can't afford his $8000 quote right now. So I would have to insulate the roof of the basement. Is this really an ok option? or would carpet be better?

And if I can do the roof is the R-19 ok or do I need something different? Do I need a vapour barrier and if I do do I put it up first and then the insulation? OR since my basement is the area that isdamp do I do the insulation and then the vapour barrier?

If someone could advise me on this I would really appreciate it!! Thanks.

Ron6519 08-24-2011 04:23 PM

Carpet will not keep the house warmer in the Winter. Proper insulation will. In Buffalo,NY your attic would need about R-49 for the weather there. An R-19 would be good for the walls.
A damp basement requires a dehumidifier. For insulation I would fill the rim joist bays with a foamboard insulation, cut to fit. Fill in the gaps with a spray foam.
Filling in the basement floor joists with insulation doesn't really do much.

Stillwerkin 08-24-2011 04:30 PM

You can do the waterproofing yourself for far less than $8K. All it takes is the 5 gallon buckets from the big-box stores and a roller on an extension. Use fans and masks for ventilation.

As far as insulating(and this is not proffessional advice so keep asking):
The cold basement walls have moisture developing on them which increases the humidity level down there. If you insulate only the bottom of the first floor, that removes the basement from the "heated zone" which cycles interior air through the furnace and a/c dehumidifyer.

If the old carpet was smelly for that reason, the new carpet will get ruined as well.
I think the air needs to circulate through there to pick up and remove surface moisture. Perhaps adding vent windows for the summer and a few more furnace duct output registers will do the trick.

It would be better to insulate the rim joist(important), and the basement walls(either from the inside or the outside). Making sure the yard grading drains surface water away from the house and downspout extensions will also help keep the basement dry.

ashory 08-24-2011 09:36 PM

I guess I am still a little confused :wink:

So I should do the rim joist bays with the board and foam, I get that part. However, I can't insulate the basement walls because it is too damp down there wouldn't that cause mold issues or if there is already a mold issue potentially worsen it? Not to mention the walls are just straight up poured concrete there are no studs or anything to put insulation between.

Putting the R19 pink fluffy stuff on the ceiling of the basement really will do nothing? Is the insulation in the rim joists really going to make that big of a difference?

If I can't do the walls and doing the ceiling will do nothing what else can I do?

The water proofer who gave me a quote also suggested a dehumidifier but cautioned me on the cost of running it. The dehumidifier isn't going to solve my problem and the basement will continue to get damp so the dehumidifier will constantly be working to keep it in a good humidity range down there.

He also said painting the walls with the special paint stuff really isn't the greatest idea as all it will do is trap the moisture between the wall and the layer of paint. Which you can see is actually happening as the paint on the wall is bubbling out and when you pop the bubbles there is the calcium build up.

The 8k quote was to dig up the perimeter of the basement and put in a new drainage system as well as install a sump pump which I don't have at the present time. My house was built in 1947 and he says nothing has been done with any of the drainage issues as the floor has not been disturbed. Could my FIL who has SOME experience with this kind of thing do that himself or is it advisable to have a pro do that?

Yard drainage is an issue and we have known that and plan on doing something about it as it gets cooler. We are also planning on installing new gutters to get water further away from the house we just kept putting it off until the guy told us really how important it was.

Ron pointed out the attic area and I hadn't thought to check there and it is insulated but from what I gather it really isn't... the previous owners nailed up some of the rigid foam board and after a little googling I see that has an R value of 10 IF we are lucky so I will be replacing that!! Hopefully then my second floor will then be livable during the winter.

Right now however I need to know any other solutions for insulating the basement without having to do the walls. :wink: Is there something I can do with my furnace and the ducting to make it more efficient?

I don't think I like owning my own home especially in this cold a** climate!:laughing:

Ron6519 08-24-2011 10:28 PM

You have a myriad of issues to address. The one that will save you the most money is proper insulation. What does, "... the previous owners nailed up some of the rigid foam board", mean?
Three important things about insulation are:
1. Use the correct amount for your region.
2. Install it in the correct place.
3. Use the most effective material you can afford.
The floors get cold because the rim joists aren't insulated. The cold air just penetrates through them and under the floor
The basement moisture issue you should deal with, short term, on your own. Make sure the grading next to the house is pitched away from the structure. Install gutters where they're needed. Extend leaders away from the houses foundation at least 3 feet, longer if you can. Installing drywells 10-12' from the house will also help, though not really a DIY project.
Yes, the dehumidifier will run a lot. That's just the way it is. I run one from May to about October. I have a finished basement and I want to control the moisture.
Do a search on "Insulation placement" so you know where to put it and how much you need.

heybales 08-24-2011 11:24 PM

Insulating unfinished basement, First time home owner please help!
You ask why not do the ceiling/floor joist insulation?
Because, unless you are ready to make a thermal break between the basement and the rest of the house, really making it a glorified crawlspace, there will be air movement through out the space and it won't either work at all, or be grossly inefficient for the money spent on it. Your carpeting wasn't really insulation, maybe up to R-3, just felt better than wood floors.
Making a thermal break is where the vapor barrier would come in.
But you would have to do so much to accomplish that, and you may want to use the basement for more than just non-temperature controlled storage you would end up with.

You ask a reason for the rim joist insulation?
It's because the rim joist is only 1.5, maybe 1.75 inches on that older home, in width. And wood is not a great insulator, you are getting maybe a whole R-2 there. And it's probably 10/12 inches tall, so a big band for cold to seep in right at floor level. Several layers of rigid foam will help a lot.

Better insulation in the attic would probably pay for itself in one winter. DIY blown-in cellulose is cheapest. Yes to a vapor barrier on the warm side there.

Another quick temporary solution for this winter until the other stuff can be done does involve your HVAC system, ducts and registers specifically.

Hot air goes up. And in the winter air is usually dryer.
Combo that effect by getting more warm air into that basement.
As it warms up there it will become more humid. And humid air in the winter can actually allow you to feel comfortable though slightly cooler.
And with the heat making it's way up, that floor should feel much better.
Didn't hear about a 2nd floor, but if there is, it may already get too hot in the winter.

You hopefully can find the duct work main balancers, mark their position before moving them, just in case they were correctly done, unlikely as that is.
And now figure out how to get more heat into the basement using those.
Like if a branch takes off for the basement, and rest continues upstairs, should be a balancer there to direct more air for the basement.
The actual register louvers won't be as useful, unless you just close them on say the 2nd floor, or a few on the 1st floor, to get more air into the basement. But the big dampeners/balancers would be better to find and use.

This may even have some positive side effects.
More humid air should help with the normal winter wood drying out and moving probably, especially if this house in it's life has been very airy, with furnace running a lot in winter.
If the major attic insulation and helpful rim-joist insulation make a big difference on heat loss, a future furnace/ac replacement should allow for smaller units to purchase, and better comfort too.
If the mostly heated basement still shows water stains on the walls in a few places, it may help indicate where you really need to address some outside water redirection issues. Perhaps those are the only/main culprits for damp basement. Wouldn't that be a great discovery!

ashory 08-25-2011 08:16 AM

What does, "... the previous owners nailed up some of the rigid foam board", mean?

My house is a Cape Cod, so I really don't have that much of an attic... On my second level, which with the current "insulation" gets FREEZING in the winter and super hot in the summer (100f+), there is only two bedrooms. When you get to the top of the stairs you can go either left or right into one of the bedrooms. Both have attic space access but the space is small you can't stand in it and it is not very wide but both go the length of the house. The master bedroom has access to the attic space at the front of the house and the other bedroom upstairs has access to the attic space at the back of the house. In those spaces the prevoius owners have attacehd rigid foam board to the inside of the exterior walls, nailing it to the framing. So if you were to crawl into one of the spaces and look straight ahead you are looking at the exterior wall of the house (the other side of it would be outside) and all over the wall you can see is the foam board that they attached. This might be ok if they had put more insulation between the wall and the foam board they attached but I don't think there is anything. Does this make sense? I don't know the correct terminology. If it doesn't I could try to create a diagram at home to show you what I mean.

With this explanation that also rules out the DIY blown-in cellulose right? because that stuff won't stick to the walls, it normally lays on the floor of the attic doesn't it?

We will be insulating the rim joists this weekend and fixing the gutter issues outside.

With the ducting you are suggesting I should install a vent that directs air into the basement? Wouldn't that lead to less air being directed to the floors above?

Would having my ducts cleaned by a pro be beneficial?

Thanks for all of your help and sorry for so many questions!

heybales 08-25-2011 11:44 PM

Great description of house, that helps.
Duct cleaning - won't help with this situation really, unless big chunks of building material was left in there preventing good air flow.

Fit those rim joist foam boards in as many layers as can fit above the foundation wall. So if you can buy 2" thick board, you may get 3 layers in there against the joist.

You don't have any air supply in the basement already? Are you really planning on using it for more than like just shed type storage? Perhaps it would be good to make it an un/semi-conditioned space. But if you plan on having a play room, exercise room, laundry room, ect, down there, then it needs to be conditioned, and should have air supply.

Yes it would rob some air flow from elsewhere. But heat rises, and unless it is lost leaking out in the basement (and you are fixing that big time), it will rise. Especially if there are doors to the basement left open. So with a few other quick easy non-pricey fixes you are doing, the extra heat thrown in down there will still make an improvement.

If you only intend to use the basement for storage and don't need it conditioned, then that changes the whole game really. Let us know about that decision.

Regarding your attic/wall insulation. So you basically have 3 triangles of unconditioned space around those 2nd floor rooms, and the 2 side triangles should have 2 insulated sides, and the top one should have one.

So the foam board on the walls of those upper rooms, that is a method. Batt insulation pushed into the stud bays would be another way to go.
Suggestion, take the foam board down, because if it is attached to the outside of the studs, and not right against the sheetrock of the inside wall - they did it wrong. There is just a big air gap in there (unless as you wonder they did put in insulation), and unless they sealed it perfectly, that foam board is doing nothing. Now, if there is batt insulation in the stud bay behind the foam board, leave it up.
The other issue is probably at the bottom of the wall, as looking at it from the attic side of the wall. So crawl back in there, and see if the board comes all the way down, and creates an air block against what is the ceiling of the room below.
In other words, what many times happens is, between the floor of that upper room, and the ceiling of the lower rooms, is a joist bay. If air can come in from the cold attic space and flow freely into that space, meaning there is no insulation in there either (and there shouldn't be with a room above the space), then you have a great place for loosing heat with cold air circulating under the floor and above the ceiling of those rooms. Which means heat never rises up to help those rooms much.

There should be blocking in each joist bay so air can not flow under those upper rooms. Use the foam board to do that.
Now you can do cellulose on the attic floor. And what about the small triangle attic above those rooms? Or are they not flat ceilinged but follow the point of the roof all the way up? Let's hope they insulated that space while allowing roof deck ventilation. You can probably discern from the attic space on that too.

Now, that sounds like a lot of work, and it is. The following would be easier.

If this description doesn't make much sense, I'm guessing your upstairs rooms are like drawing A, or were kind of attempted to be insulated like A. But B is easier, and relies on just bat insulation. And with faced batts, just staple to the roof joists.

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