do we need to add collar ties?

heyjude · August 29, 2008, 04:17:45 PM

Hi, my husband and I just built a 12'x12' guestroom on post and pier foundation. We did an open beam ceiling using a 2"x10" center beam and 2"x8" rafters. The rest of the building is 2"x4" construction and the floor joists are 2"x8" Everything is 16" OC we put 5/8ths plywood on the roof which we are about to cover with asphalt shingles. We live in the Pacific Northwest and don't get a huge amount of snow. We would like to keep the high open ceiling which we'd probably cover with T&G or drywall, but I'm now concerned that perhaps we should add collar ties to prevent the walls pushing outward. Would appreciate any input, Jude

glenn kangiser · August 29, 2008, 04:28:17 PM

Jude.

What pitch is the roof?

I don't think the 2x10 ridge board can be considered a beam but I'm not sure if the room is big enough to have a problem. I may be able to find more by looking through some plans but maybe someone who knows will drop in first.

August 29, 2008, 04:31:44 PM

I'd say atleast one in the center. Two might be better spaced 4' apart.

heyjude · August 29, 2008, 04:37:33 PM

Yes, beam is the wrong word, ridge board is what I should have said - I'm technically challenged I'm afraid!! Anyway, would two boards 4 ft apart, stretching across the width of the interior and nailed to the plate along the top of the wall studs work? Jude

ScottA · August 29, 2008, 04:46:21 PM

Be better nailed to a couple of rafters I'd say.

August 29, 2008, 04:53:52 PM

More effective than collar ties would be lower, at top of wall and secured to rafters and top plate. For the 12 foot length I believe two, spaced equally would be the ticket to prevent a slow spread (walls) and sag (rafters) over time.

Collar ties as low as you can stand them give better restraint than collar ties way up near the top.

glenn kangiser · August 29, 2008, 04:57:48 PM

Quote from: heyjude on August 29, 2008, 04:37:33 PM
Yes, beam is the wrong word, ridge board is what I should have said - I'm technically challenged I'm afraid!! Anyway, would two boards 4 ft apart, stretching across the width of the interior and nailed to the plate along the top of the wall studs work? Jude

Don't feel like the lone ranger, Jude. I have a time with a lot of the proper terms too. I'm a steel guy and humble, lowly volunteer here.

heyjude · August 29, 2008, 05:03:33 PM

Thanks for your advice everyone.....Jude

glenn kangiser · August 29, 2008, 05:06:57 PM

Our pleasure Jude.

FWIW I think what the others are saying is reasonable also - I'd even consider bolts and glue.

Feel free to post pix if you have them.

August 29, 2008, 05:36:18 PM

Jude. If I understand your original post you said you were using an open beam ceiling. If that is the case I would opt for a heafty 4 X 8 bolted to the rafters than just using 2X material. If it is an open beam ceiling it would be more pleasent to look at. Maybe you are calling an open beam when in fact it is a cathedral ceiling. Just my $.02 worth.

heyjude · August 29, 2008, 08:18:23 PM

We're leaning towards a couple of heavy beams as you suggested, bolted to the rafters, I'll post some photos when it's done. Thanks again for all the advice. Jude

Redoverfarm · August 29, 2008, 09:20:25 PM

Jude although I really don't have a straight on photo of the collar ties there is one picture that shows a portion (3 pictured between the fireplace and soon to be loft bathroom). They are 4X6 (3-1/2 X 7-1/2) in the loft ceiling of my cabin. When I get to it there will be Tounge & Groove ceiling which will be cut around them. Wish I had a better picture.

This is the opposite direction but the one shown will be mainly decorative to match the others as I have a bathroom partition at that location

This is an actual log collar tie that sits overtop of a ceiling beam in the livingroom.

Woodswalker · August 31, 2008, 12:57:27 PM

In my cabin build, I used exactly the same dimension materials for a vaulted ceiling as you are doing. The dimensions are larger (16' x 20') though, and the pitch is 6/12. I bolted 4, 2 x 10 collar ties to the rafters, about half way between the height of the wall tops and the ridge board, and have left them exposed. It has now gone through two winters, including 3' of snow on the roof last one, with no spreading or other issues. The whole roof structure seems extremely solid.

Welcome to the forum and keep on build'n.

Steve