I have a pole barn-type roof on an outbuilding, about 30 years old. I periodically find that a leak has started, apparently around a screw hole. I have tightened all the screws, but some no longer tighten. Should I just apply some stuff over the screws, such as "Through the Roof" sealant? Would that be a long-term solution? Or will it be a problem some day?

Hoping someone on here can give us some guidance. 11 years ago we had a new asphalt 3 tab shingled roof installed on our house along with a new ridge vent. The roofing contractor inspected the plywood prior to installation and found it sufficient to paper and shingle over. They had said that their work was guaranteed against defects in workmanship (nothing in writing..I know..big mistake). The roof performed well for the first 9 years at which point a leak developed in a spot on the far side of the house about 5 ft down from the ridge vent. We called the company who sent over a roofer who said the issue was the ridge vent probably popping up from the fasteners, thereby allowing water to get through. They re-sealed the vent and put "more substantial" nails through the vent. At that point, they did stand behind their work. No complaints. Last week, another leak surfaced around the same spot as the last leak..maybe about 1 ft away from the other one and closer to the ridge vent. We called the contractor and after a few days, they sent someone out to inspect. in the meantime, I went up in the attic and looked at the issue from the inside. The plywood underlayment had cupped about 1/4-1/2" at the spot of the leak. There was delamination on the plywood and witness marks of moisture were apparent at or near the plywood seam. We explained to the contractor that due to the intrusion, the plywood was damaged and would have to be replaced. They sent the guy out who re-adjusted the ridge vent and left without touching base with my wife before leaving (I had been at work when this happened). When I got home and went back up in the attic, the plywood had not been replaced. FYI, my wife explained to him when he got there that the plywood had been damaged and would need to be addressed. I sent the contractor a picture of the plywood so they could see the damaged piece along with a request that if it wasn't going to be replaced due to the water intrusion, then I would like a letter from them stating that they had seen the picture and based on the image, it was not an issue (knowing full well that I probably wasn't going to get a letter from them). Fast forward to today. The contractor's "Operations Manager" called my wife while I was at work and refused to replace the plywood. They said the issue was because, "[i]The ridge vent is 11 years old and when they were made back then they were prone to leaks. You need to get a brand new vent installed by us that are guaranteed not to leak like the old one [/i]". Also, "[i]The cause of your leak isn't due to faulty workmanship. The problem is due to snow pack on the ridge vent pushing the vent down, thereby popping the nails and causing the leak[/i]". As such, they aren't liable to repair the plywood since it is essentially a weather related issue "[i]If a windstorm came and dislodged the ridge vent, you wouldn't expect us to repair it for free, would you[/i]?" Now, I do home improvement stuff frequently but I'm the first to admit that I'm an amateur when it comes to roofing. However, these explanations seem like total BS. For one, I'd think a properly installed vent no matter the age would be leak tight if installed properly and I've never seen snow pack on a roof cause those substantial vent nails to just pop out (mind you, we have a raised ranch with a 5/12 pitch). I'll include the picture of the plywood for your evaluation. I think this will cause an issue down the road if not dealt with but I think the contractor would be somewhat liable since the issue seems to stem from the install. The guy did admit that the shingles were evaluated and were in "great shape". So if you guys could give me some direction as to where to go with this if the contractor steadfastly refuses to replace the plywood. A couple people have mentioned having the work done by another contractor then taking this contractor to court for the price we paid for the repair for refusing to repair the issue. Someone else said to have them submit in writing their evaluation where they are saying the issue is a faulty ridge vent due to inadequacy because of age and snow pack weight, then going to GAF (who made the vent) and have them refute the answer. In any event, I will take any advice you all can provide. Thanks! P.S. - I should add the only reason I would be pursuing this would be the contractor's policy of, "We stand behind our work. If there is ever a workmanship problem, give us a call and we'll make it right". [img]https://cimg4.ibsrv.net/gimg/www.doityourselft.com-vbulletin/2000x1504/img_20210714_173509933_3521219944f4f8b0f990b3919132394f01a10233.jpg[/img]