Originally Posted By: Jay Moge This post was automatically imported from our archived forum.
i’ve seen many many saggy roofs here in N.H… some require immediate repair, some need reinforcing, and some just need close monitoring. the first winter of a newly constructed home is crucial. the new wood is still “seasoning” and will amplify over the years. ventilation also plays a factor and is usualy corrected shortly after found, but by the time the house is sold, the damage has been done. improperly seasoned wood is doomed from the get go if all the “wrong” conditions are present. even after corrected the process still continues, only slower. hope that cleares it up a little for you.
Originally Posted By: dandersen This post was automatically imported from our archived forum.
The supports against the rafters should be constructed of two pieces of 2x nailed perpendicular to one another, creating a stiff back which will not sag under load, heat and moisture changes.
Originally Posted By: loconnor This post was automatically imported from our archived forum.
Thank you, everyone for your feedback. This house has been empty for about a year. I was very surprised how cool the attic was, given the warm temperature outside. The ventilation to the attic consisted of large gable vents, with the roof vents installed toward the ridge. But no eave vents at all.
The vertical supports you see in the photos, are attached to the ceiling joists. I thought that would put undue stress on the ceiling joists resulting in cracks along the ceiling and walls, but there are no indications that I can see.
Originally Posted By: mcyr This post was automatically imported from our archived forum.
Larry;
It is pretty obvious to me from what I see that the framing was undersized for this low slope roof. There is no evidence of collar ties nor knee wall support.
The framing in general really is bad and some to the pictures indicate bowing.
It appears that some bracing was added over the years using the chimney as a prop. The blown in insulation was also upgraded noticing the moisture that affected the roof boards.
Would strongly recommend an SE on this one and check out the ventilation as well.
Originally Posted By: Jay Moge This post was automatically imported from our archived forum.
Marcel. are there different framing standards on roofs depending on weather or not you are building in a “snowy” area? i mean is a roof frame in N.E. any stonger than one in say AZ?
Originally Posted By: mcyr This post was automatically imported from our archived forum.
Jay;
I would have to say that roof rafters in Maine or New Hampshire would be designed to carry more load that a geographic area with no live loads.
The IRC has tables of loading for different design loads.
I do not have the specifications handy, but the building I am doing now is designed for 40# live load and 10# dead load and L/240 if not more.
In either case a structural engineer is required to come up with the design for any particular area and should be recommended for scenarios like the previous post.
I could get in to conventional framing standards that I was brought up with, but these standards due to codes have changed.
Originally Posted By: Jay Moge This post was automatically imported from our archived forum.
Marcel,
yes it did help alot. i just wonder if anyone has built houses i different parts of the u.s. and noticed any major differences in building "practices" that are geographicly spacific to certian areas pertaining to roofs?
but being strictly a "mainerd" i guess you may not know how a roof in arizona may differ.(just kidding Marcel.) 
Originally Posted By: mcyr This post was automatically imported from our archived forum.
Hey Jay; I have been out of the State a bit you know. ha. ha..
I was in Florida in 1969 living with my oldest brother for 8 months and joined the carpenters union in early 1970. Part time I would help another contractor to build small residential additions.
That is when I noticed the difference in framing of roofs.
Down in Florida at that time, roof trusses were just coming into play and where constructed of 2"x4" rafters. Up in Maine the rafters would be 2"x6" rafters with 2"x6" ceiling joist.
Before trusses, the rafters were supported by knee walls on top of the ceiling joist and the ceiling joist were supported by bearing walls below.
When the truss design came into the picture, I was working with my father. He would build a W-truss with 2"x6" with a king post design.
He would nail a rough sawn 1"x6" board on both sides of the rafter and joist in the shape of a w-truss with king post design.
This was done on a chicken barn that was 200' long and span of 65'.
It was framed at every two feet and carried 2"x4" strapping at 2' on center for the metal light gauge aluminum at a 6 in 12 pitch.
Yes, the building is still standing and looks like the day it was built.
Since my home town is about 265 miles north of here I cannot provide pictures.
So, I guess you could say a 2x4 is good for Arizona, but a 2x6 is required in Maine.
Today's truss designs can accommodate for whatever geographic area you are in.
