New Home Begins

[tkappeler]

The T&G and beams look great, this is the look I want for a 24x24 addition on my home. How will you insulate and finish the roof? What is your roof pitch, and how will you deal with the splice of the two ridge beams. You have done a great job with the photo's and the home.

a layer of 4 mil poly goes down over this, then the raycore panels go down over this. The panels will run horizontally and timberlock screws will go down through the panels and T&G and into the rafters. Purlins go down vertically over that then the plywood sheathing.

As for the splice, there are 4x4x10 angle brackets that will get through bolted all around.

. They did not finish this one as we are going to swap the 8" long bolts for 7". Better than cutting them off.

edit: The roof pitch is 8/12 for this room and 5/12 for the trusses. Architectural shingles will be used.

If this question has been answered before, please excuse my brain fart for not recalling the post. Will there be some sort of caulking or other sealing on the roof deck side of the T & G boards?

The T&G does not provide any kind of structural element. The Raycore panels provide that as well as the insulation (R42).

[dave1949]

In MotorSeven's building thread about here:
http://www.tractorbynet.com/forums/p...egins-184.html

There is a long discussion about condensation forming in the airspace (probably) created by the purlins, under the metal roofing. Your roof has vertical purlins, Rick's are horizontal, your purlins have plywood sheathing on top, but the roofs are somewhat similar. What is the plan as far as venting the air gap created by the purlins in your roof?

[tkappeler]

In MotorSeven's building thread about here:
http://www.tractorbynet.com/forums/p...egins-184.html

There is a long discussion about condensation forming in the airspace (probably) created by the purlins, under the metal roofing. Your roof has vertical purlins, Rick's are horizontal, your purlins have plywood sheathing on top, but the roofs are somewhat similar. What is the plan as far as venting the air gap created by the purlins in your roof?

There are powered gable fans for the truss areas and there will also be ridge venting at the top of the great room. This is a bullet point to discuss with the roofer when he does his pre-start walk around.

edit: I remember seeing an article in the Journal of Light Construction where they were putting the purlins on the diagonal for metal roofing specifically to address the moisture/convection blocking issues with putting them on the horizontal.

[dstig1]

I don't believe 4 mil poly is sufficient there, especially if it is pin cushioned by a ton of nails. Not sure what the Raycore roof panels are for this, so maybe you are covered, but just wanting to check on that...

[mjncad]

Take a look at Post #361 New Home Begins - Page 37 as the OP covered some questions I and others have about his substantial roof system.

[tkappeler]

I don't believe 4 mil poly is sufficient there, especially if it is pin cushioned by a ton of nails. Not sure what the Raycore roof panels are for this, so maybe you are covered, but just wanting to check on that...

Here is a cutaway photo of the roof system. Our T&G sits on top of the rafters, then the panels go over that. No pincushioning.



and here is a link to the user's guide showing all of the details on how to install it and better photos.

[dave1949]

It seems there are choices:
: OSB roof sheathing fastened directly onto the integrated wood in the raycore panel, then a normal shingled roof.

: vertical purlins fastened to the integrated wood in the raycore panels (cold roof), not sure what a cold roof is.

: metal roofing attached directly to the integrated wood in the raycore panels.

For the roofers here, what are the pros and cons of these various methods?

[tkappeler]

It seems there are choices:
: OSB roof sheathing fastened directly onto the integrated wood in the raycore panel, then a normal shingled roof.

: vertical purlins fastened to the integrated wood in the raycore panels (cold roof), not sure what a cold roof is.

: metal roofing attached directly to the integrated wood in the raycore panels.

For the roofers here, what are the pros and cons of these various methods?

My understanding is that the purlins and sheathing on top of it give a cooler roof and substantially increase shingle lifespan.

[dave1949]

My understanding is that the purlins and sheathing on top of it give a cooler roof and substantially increase shingle lifespan.

I guess the idea it that outside air is cooling the underside of the sheathing the shingles are applied to.

Are your exposed beam rafters on 24" centers? The Raycore panels must (will) be oriented such that the integrated wood is running horizontally across the roof? That would seem to be the only way to get a secure connection from rafter to roof deck. Vertical purlins would cross the integrated wood, that makes sense.

[tkappeler]

I guess the idea it that outside air is cooling the underside of the sheathing the shingles are applied to.

Are your exposed beam rafters on 24" centers? The Raycore panels must (will) be oriented such that the integrated wood is running horizontally across the roof? That would seem to be the only way to get a secure connection from rafter to roof deck. Vertical purlins would cross the integrated wood, that makes sense.

The 6x12 rafters are 48" on center. The panels do run horizontal, spanning them and staggered to provide the structural support. Purlins will run vertically perpendicular to the panels.