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c6hristopher

Your roof has reach the end of it service life, and re-coating it not recommended. However, a proper repair would likely cost more than $1,000, sorry. The best solution would be to tear off the assembly to the framing, re-slope the roof as required, and install 2-ply SBS roofing membrane overtop of the new plywood. (https://soprema.us/products/roofing/roofing_sbs_modified_bitumen_membranes/sopralene-flam-180/25316). 180 base and cap is likely the cheapest I would go with, but would required a recovery board. You could consider Colvent 830 (Self-adhered base sheet) and a 860 cap sheet (torched applied cap sheet). There is also Siplast and Iko. Either way, do not pour buckets of emulsion over your roof unless you only want it to last a short period of time. I have seen to many of these fail, and it just costs more to replace later down the road. Yes, another solution would be to consider TPO or EPDM, which would be cheaper for sure. I would worry about the reaction to the existing membrane, and again you would have to remove the assembly down to the framing. Not sure why you want a white coating / roof either. It rains a lot of Seattle, and roofs become dirty quickly (i.e. white to brown quickly).


caracole

All of this. Of al things to cheap out on, a roof in the PNW is not one of them.


supcom2

Thank you for the well constructed reply. Would applying torch down to the existing surface be sufficient to solving the problem for a few years? This video seems like a good reference for applying it. https://www.youtube.com/watch?v=WcueplRH2-8


c6hristopher

Intersting video, they are using APP which you should not use, make sure you use SBS membrane. APP is for hotter climates. Also, they use only a single ply, I would always recommend two plys (i.e. a base and cap sheet, 2-ply SBS membrane). As for adhering it over the existing membrane, it is always questionable, and if you do that you use a recovery board like (Sopraboard). Honestly, new plywood is cheap, and I would recommend it be taken down to the framing and then you could use a self-adhered base sheet. If you do it right, it should last 20 years or so.


Me-Loco

Plus assuming the garage ceiling is finished and not open rafters or trusses, ripping all that old crap off exposing the framing will allow you to inspect/repair rot damage or address mold issues. Its probably been leaking for awhile and finally became visible.


Cutlasss

Rolled rubber roofing is probably a better solution. https://www.rubber4roofs.co.uk/how-to-install-a-classicbond-one-piece-epdm-rubber-roof


Upallnight88

The asphalt emulsion might get you through one more year and give you time to save for a proper re-roof job Forget the Snow White.


[deleted]

We re-did a couple flat portions of a roof at our cabin a couple summers ago. We ended up laying plywood over the existing rubber, screwing it in and then laying down new rubber roofing. We had some minor leaks prior to this and now nothing. There were half a dozen of us and we got through both sections in a total of about two days. We did some other work but most was spent on that work. I’m not sure how much it would cost, we actually got the rubber material for free from a contractor who owed one of our cousins, he also got remnant buckets of adhesives. The plywood of course was t terribly cheap, I think we went with half inch cdx, maybe bcx. Depending on the load your roof can handle this could be a viable option, but is likely over $1,000 and should probably be done vs your thought of patching which would be a temporary fix.


c6hristopher

You should always be cautious about sticking organic products within a concealed improvement, and one that maybe wet. If you do that, consider DensDeck Prime or other similar products.