Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Insulation/attic baffles

DDCDTX's Avatar

Join Date: Mar 2013
Posts: 4

03-30-13, 03:56 PM   #1  
Insulation/attic baffles

I have been perusing this forum as well as others as I was looking at adding more insulation on top of the amount the builder put in in 2004. I noticed that I only have 3 or 4 attic baffles in the entire attic, even though I have soffit around the entire perimeter.

With the lights off on a sunny day, I only see light coming up from these 3 or 4 baffles. I'm assuming some of my soffit is clogged. The way my roof line is setup it is very difficult to to get down to the edge, I can't even get close.

Any tips on how to install these baffles with the limited space? I read somewhere that you can remove the soffit if needed. I figure I should do this before blowing more insulation in. Not sure what the builder was thinking only putting 3 in...Name:  IMG_1495.jpg
Views: 7985
Size:  38.2 KBName:  IMG_1496.jpg
Views: 6615
Size:  38.9 KBName:  IMG_1497.jpg
Views: 5131
Size:  36.5 KB

Pictures attached. Thanks!

Sponsored Links
stickshift's Avatar
Group Moderator

Join Date: Oct 2004
Posts: 18,476

03-30-13, 04:08 PM   #2  
Welcome to the forums.

If you can't get to these areas to remove the insulation, then I would be looking at dropping the soffit (ugh, what a mess that would be).

XSleeper's Avatar
Group Moderator

Join Date: Dec 2004
Posts: 19,279

03-30-13, 06:02 PM   #3  
Attic ventilation is often a topic where there are various schools of thought. One of the most popular is that attics require 1 sq ft of ventilation for every 300 sq ft of attic space. That's not much. It's also to be divided equally (or nearly equally) between intake and exhaust. The fact that your entire soffit is ventilated and you only have a few soffit baffles is not the point. The point is, how many sq in of intake (your soffit baffles) do you have... how many sq in of exhaust do you have... and what is the sq ft of the attic space? Then see if that is within the 1:300 ratio or not before you start adding more vents.

I understand that in Texas, people are probably more concerned about heat buildup in their attic, and think that more ventilation is better, to help with air conditioning bills. I can't argue with that sort of logic, but you should also realize that the more ventilation you have, it will also produce a colder attic space in the winter, which would then take more energy to heat the house in the winter. So that would be one reason why "more ventilation" is not necessarily better... and would be the reason why there is a recommended level of ventilation. (see: BSD-102: Understanding Attic Ventilation — Building Science Information)

Plugged baffles is another issue, and that should be corrected... it could be easily remedied by snaking a long 1 1/4" shop vac hose down the baffles and sucking out the insulation that is plugging them up. You could lay a few small pieces of plywood down on top of the ceiling joists to give you some better working conditions. Baffles should be long enough that they do not get plugged with insulation, so yours need to be extended higher by adding another section of baffle onto the existing- especially if you intend to add more insulation. Under the right conditions, high winds will blow air INTO the soffits on the windward side of the house, and if there is enough air pressure, that air will exhaust not only out the ridge, but also out the soffit vents on the leeward side of the house... taking some insulation along with it as it blows across the attic floor, if the baffles aren't high enough.

Bud9051's Avatar

Join Date: Oct 2008
Posts: 9,764

03-30-13, 06:08 PM   #4  
If your soffits are vinyl or something else that can be removed, as mitch said it is one solution. They make baffles that flop down into the soffit to block the insulation during install and to block wind the rest of the time.

I know you want to do this, but the insulation contractors do this ALL the time and they have specially built skinny people who have no problem getting all the way into those tiny spots. I'm not one of them. In any case, it would be worth getting a bid or two.

You asked "Not sure what the builder was thinking only putting 3 in." Yes you do, $$$$$

In addition to more insulation, take care of some air sealing before you fill the attic, at least any major areas.


DDCDTX's Avatar

Join Date: Mar 2013
Posts: 4

03-30-13, 09:27 PM   #5  
Thanks for all the replies.

So from reading above, assuming the 3 or 4 baffles are clear, that could be enough intake? The attic is ~2200 sq ft (1800ft living with insulation, 400ft attached garage that has no insulation at all in the attic, but is drywalled below.) so if there are 3 @ about 2 sq ft each that is enough to cover 1800 sq ft? I think I just have two stationary (non-whirlybird) circle vents, at most 3, with no ridge vents.

I also noticed after poking around with a rake that they put the rolled fiberglass along the edge, then blew in on top of it.

When you say sealing, do you mean around areas like the stairs into the attic (they are inside the house)?

Edit: My sofits are hard-plank or some other type of concrete board, not easily removed.

Nashkat1's Avatar

Join Date: Mar 2012
Posts: 8,470

03-31-13, 10:12 PM   #6  
assuming the 3 or 4 baffles are clear, that could be enough intake?
It isn't about the area of the baffles, it's about the area of the intake vents. For the 1800 ft.[SUP]2[/SUP] insulated ares you need between 6 and 12 ft.[SUP]2[/SUP] of ventilation opening, evenly divided between intake and exhaust. It should be as continuous as possible.

I also noticed after poking around with a rake that they put the rolled fiberglass along the edge, then blew in on top of it.
You need to pull all insulation out of the soffits, and open the path up into the attic from those.

Search this Thread