Remodeling the basement.. - Page 2

Fordguy64 · 01-19-12, 08:19 PM

Well the house is brick not sure if that makes a big difference with the way the joists are.. Part of the problem with the two part is I kinda have to do this thing in stages.. Mainly because there is duct work that runs down the corners of the ceiling... I would have to take all of that down and prep for the foam and put it all back up since its only in the 40s during the day and tonight it's supposed to be 15 out.. Now I know the 2 part is the better option and I'm not one to usually skimp on things like that.. I like to do things once so I could end up going with thoe two part foam.. As far as leaks go there are only 2 that I'm aware of and that was because we got some record amount of rain I think it was 2 inches in an hour or something crazy like that.. Both are very minor and I know exactly what and where the sources of those are.. Both being gutters.. The house is getting a new roof and gutters come spring time..

S-F · 01-20-12, 11:57 AM

Quote:

Originally Posted by Fordguy64

The house is getting a new roof and gutters come spring time..

Do you have a hot roof? If so putting a new roof on is the perfect opportunity to put 6" of polyiso on there. About the foam, you've really got to do it. Either that or spend a small fortune on caulk and then spend a week or so applying it. The HVAC guy I deal with has told me on more than one occasion that the average houses he deals with (which is probably tighter than the average house) loose about 10% of their heat through that area.

Fordguy64 · 01-20-12, 12:12 PM

Not sure what a hot roof is?

S-F · 01-20-12, 12:20 PM

No ventilation

Fordguy64 · 01-20-12, 01:53 PM

Ah lol shoulda guessed that.. it has no soffet vents but it does have vents in the peaks.. I have three peaks 2 have small vents and the other has a larger vent with a temp controlled fan.. no other vents that I can see

S-F · 01-20-12, 02:04 PM

So you have an attic? If so it's a cold roof. If there are no soffit vents you could turn it into a hot roof and finish the attic later on down the road. And please, put a metal roof on.

Fordguy64 · 01-20-12, 02:41 PM

Yes I have an attic and I will look into the metal roof also what are the beifits of a hot over cold roof?

S-F · 01-20-12, 04:26 PM

Quote:

Originally Posted by Fordguy64

what are the beifits of a hot over cold roof?

Cold roof is much easier to deal with because you, theoretically, have a lot of air movement via convection up there to keep the temperature equal across the entire roof deck. If you don't have a ton of soffit venting and you have a bunch of ridge/upper gable venting you are actually doing pretty bad as this created a negative pressure situation in the attic sucking any warm air possible through your ceiling. You should have considerably more lower ventilation in a roof than upper. But you do need both. A good combination of continuous soffit vents, a ridge vent and gable vents is ideal. I add gable vents in there where many people don't because when you have a super insulated attic the snow doesn't melt off the roof. Then your ridge vent can be covered with a foot of snow or more. It vents next to nothing that way so some gable vents will help. When you have more lower ventilation than upper you create a positive pressure situation in the attic which fights the convection which tries to draw your heat out of the house through your ceiling. A cold roof is really only for when you have a portion of the interior space abutting the roof. There are really only two instances where this happens: one is with a cathedral ceiling and the other is in a situation like a cape or, to a lesser degree, Daox's house where he has only about a foot of slope which meets the roof. In the latter two situations it's usually preferable to completely bring the kneewall crawl spaces into the thermal envelope and make the roof hot from the soffit to the top of the slope. You could put gable vents and a ridge vent in but there is really no reason. Just seal it all up.

So, long story short:

If you ever have plans on bringing you attic into the living space or have any portion of the living space in contact with the roof assembly, go for a hot roof. One of the reasons I bought a ranch is that the attic is so easy to deal with. Just install good insulation baffles, seal everything up with a vengeance, put a metric s*@t ton of cellulose on top and stop being cold.

EDIT:

I'd like to amend my statement about dealing with a house like Daox's and in the process give and easy way to cope with lack of ventable soffits. There can also be gable vents down low in the gable. Little square things. You have to keep in mind that the lower ventilation area needs to be much greater that the upper. So you may want to install a full bank of maybe even two rows of these vents on the gable ends from rafter to rafter. You see, Daox has a big attic. It's just that he has this small portion of roof deck that's only, what, 8 inches? from his living space. If you meet code and have 1.5" of ventilation space in there you're only talking about R 20 or so (unless you go the spray foam route) where you could EASILY have R 60 in the main attic. And let's not forget the thermal bridging. That should be clearly visable in such a situation. On a frosty morning you'd be able to see that 1' stretch across the roof with 1.5" wide spots of no frost every 16" OC as the rafters conduct that heat.

Attics rock. No better way to break thermal bridging than to keep the outer surface 8' away from the conditioned area. We should do this with all of our houses on all sides.

1 more thing. Those attic fans (I'm not talking about whole house fans here) aren't a great idea. Waste of juice. Just install some real ventilation down low and let the laws of physics do the work for you. Then figure out how much it cost to run, set that money aside and buy your wife a pair of earrings or use it to justify taking a day off from work to take her out to lunch and rub her feet in the afternoon.

Wish you weren't in Ohio so I could come over and help you with your projects. Can't we get some ecorenovators in Western MA?

Fordguy64 · 01-23-12, 10:20 AM

good info thanks S-F..

I have a metal roof company coming out today to talk to me about a roof..

now back to the basement..
The ceiling of the basement is all insulated.. i planned on taking it all down.. do you think its worth taking that insulation up into the attic since i only have less that 6inches of insulation up there? i plan on insulating all that after the roof..

S-F · 01-23-12, 10:23 AM

Putting cellulose on top of fiber glass generally isn't a good idea. Rodents tend to not nest in cellulose (although it certainly doesn't deter them like some will lead you to believe) but they for some reason absolutely love to live in fiberglass. Go figure. If you put cellulose on top of fiber glass you are making their rodent condo that much warmer. Aside from that, putting the fiberglass up there won't hurt. Just don't expect too much from it. An other thing to think about is sound isolation between floors. If you aren't going to be putting drywall up for a ceiling you might want to keep that fiber glass up there to deaden sound. You will have to cover it with something though.

Also, DIY metal roof is pretty easy. I'm sure there are youtube videos about it or something like that.

01-20-12, 02:41 PM	#17
Fordguy64 Journeyman EcoRenovator Join Date: Oct 2011 Location: Cincinnati ohio Posts: 338 Thanks: 40 Thanked 35 Times in 31 Posts	Yes I have an attic and I will look into the metal roof also what are the beifits of a hot over cold roof? Last edited by Fordguy64; 01-20-12 at 03:08 PM..

01-23-12, 10:23 AM	#20
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	Putting cellulose on top of fiber glass generally isn't a good idea. Rodents tend to not nest in cellulose (although it certainly doesn't deter them like some will lead you to believe) but they for some reason absolutely love to live in fiberglass. Go figure. If you put cellulose on top of fiber glass you are making their rodent condo that much warmer. Aside from that, putting the fiberglass up there won't hurt. Just don't expect too much from it. An other thing to think about is sound isolation between floors. If you aren't going to be putting drywall up for a ceiling you might want to keep that fiber glass up there to deaden sound. You will have to cover it with something though. Also, DIY metal roof is pretty easy. I'm sure there are youtube videos about it or something like that. Last edited by S-F; 01-23-12 at 10:26 AM..

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01-19-12, 08:19 PM	#11
Fordguy64 Journeyman EcoRenovator Join Date: Oct 2011 Location: Cincinnati ohio Posts: 338 Thanks: 40 Thanked 35 Times in 31 Posts	Well the house is brick not sure if that makes a big difference with the way the joists are.. Part of the problem with the two part is I kinda have to do this thing in stages.. Mainly because there is duct work that runs down the corners of the ceiling... I would have to take all of that down and prep for the foam and put it all back up since its only in the 40s during the day and tonight it's supposed to be 15 out.. Now I know the 2 part is the better option and I'm not one to usually skimp on things like that.. I like to do things once so I could end up going with thoe two part foam.. As far as leaks go there are only 2 that I'm aware of and that was because we got some record amount of rain I think it was 2 inches in an hour or something crazy like that.. Both are very minor and I know exactly what and where the sources of those are.. Both being gutters.. The house is getting a new roof and gutters come spring time..

01-20-12, 12:12 PM	#13
Fordguy64 Journeyman EcoRenovator Join Date: Oct 2011 Location: Cincinnati ohio Posts: 338 Thanks: 40 Thanked 35 Times in 31 Posts	Not sure what a hot roof is?

01-20-12, 12:20 PM	#14
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	No ventilation

01-20-12, 01:53 PM	#15
Fordguy64 Journeyman EcoRenovator Join Date: Oct 2011 Location: Cincinnati ohio Posts: 338 Thanks: 40 Thanked 35 Times in 31 Posts	Ah lol shoulda guessed that.. it has no soffet vents but it does have vents in the peaks.. I have three peaks 2 have small vents and the other has a larger vent with a temp controlled fan.. no other vents that I can see

01-20-12, 02:04 PM	#16
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	So you have an attic? If so it's a cold roof. If there are no soffit vents you could turn it into a hot roof and finish the attic later on down the road. And please, put a metal roof on.

01-23-12, 10:20 AM	#19
Fordguy64 Journeyman EcoRenovator Join Date: Oct 2011 Location: Cincinnati ohio Posts: 338 Thanks: 40 Thanked 35 Times in 31 Posts	good info thanks S-F.. I have a metal roof company coming out today to talk to me about a roof.. now back to the basement.. The ceiling of the basement is all insulated.. i planned on taking it all down.. do you think its worth taking that insulation up into the attic since i only have less that 6inches of insulation up there? i plan on insulating all that after the roof..