I recently purchased a townhome in Washington DC. I’m getting quotes for contractors and most are pushing modified bitumen rather than rubber or EPDM.
What should I ask for when considering this material? 1,2,3 or 4 ply? I like the idea of a white granulated modified bitumen at 2 ply. The granulated is maintenance free and the white would reflect uv and heat better.
Also, how can I best negotiate with any potential contractor to get the price down? Thanks!
You can say “This is all I am willing to pay”…And if he is still in business when you have a problem,maybe he will come back…
That is the problem…People want a service,and want a good job,but want it cheap!You can’t get the best job done CHEAP…You can however get a quality job done for a reasonable cost…
poster could be a politcian.
first i do not like 2 and 3 layers of
anything unless it is hot tar with layers of
torchdown last for 20 plus yr just one layer.
if water gets between the 2 layers it becomes
a big problem verses 1 layer were when it leaks
its easy to fix.
roll roofing whatever the style should not be
get one layer nice and tight with no leaks.
thats hard enough.
i have been doing modified for 25 + yrs & recommend atleast 2 inches of insulation, a 3 ply, with awaplan 170 white mop applied cap sheat on top of the 3 ply. it will look beautiful & outlast all of us. in that area call j&r roofing out of jessup, md.
I used to work with J&R quite a bit years and years ago. I believe they were the ones that roofed the White House if memory serves me correctly.
Anyway, I would recommend polyisocyanurate insulation, a coverboard like Densdeck or the cheaper alternative of perlite or fiberboard. Install a base sheet, 3-plies of asphalt BUR with Type IV felt and Type III asphalt, then install a reflective APP modified bitumen membrane. If you don’t plan on walking on your roof alot, and assuming you are willing to pay a little more, I’d recommend DerbiBrite by Performance Roof Systems. The APP membrane can either be torch-applied or set in cold-applied adhesive and only the laps torch fused together.
Where is your building insulation located? On top of the roof, or on top of the ceiling?
If it is a 1908 townhome, then its probably on top of the ceiling. Polyisocyanurate bord would not do any good in this scenario.
I would, however, agree with making sure you get a nice flat secure substrate down, though. You probably have a plank roof deck at thi point. Plank roof decks tend to porpoise over time. New plywood, or better yet, like Cerb said, a Dens deck recover board then a base sheet and mod bit cap. I like two layers of modified if youre not going to set the base in hot tar.