It is typical for the roof to be in this condition for 30 60 days while other phases of the construction are completed.
Rain on tar paper roof.
Normal delays and the rain you indicated will not affect the structural properties of the panels.
Over a long and i mean long period of time the sun heat will dry out the.
Certainly it would have been better to have covered the roof with a tarp or roofing felt before it rained.
By carlye jones roofing felt also known as tar paper serves as both an extra layer of protection between the shingles and the plywood and as a temporary moisture barrier until all the shingles.
When tar paper gets wet it buckles and ripples.
Our osb is rated exposure 1 and that means that it will withstand normal delays in construction.
Traditional roofing felt also called tar paper or underlayment is felt saturated with bitumen also called asphalt.
Osb like all other wood will expand.
Roofing felt is made of compressed polyester or fiberglass fibers.
It sounds like the tarpaper covering this is the old tar paper correct.
I wouldn t trust it in the rain but it s not my job.
Bitumen or asphalt is distilled from petroleum and is what makes roofing felt waterproof.
Any repairs would be his problem.
The top is protected from the sun by stone granules but there is no such protection on the underside.