A laboured query maybe...???

[Bloosman]

Hi group...what a fantastic place....!!!!

I'm renewing the flat roof on the dormer extension on our house (1-1/2 storey high).

The old felt has been removed and I'm in the process of replacing some rotten timber decking where it has been leaking (18mm t&g chipboard used originally).

It looks a simple enough job, albeit a large area, approx. 3m x 10m.

There is a gutter to the front, with raised edges at either end. The rear joins the roof just two tiles below the ridge, with the felt under both tiles to a distance of about 300mm.

It also buts onto two chimney breasts at each end, so I'll have to do some work around them.

My question is this...should I go for EPDM or the good old fashioned 3-layer felt for a covering...? (At present the builders blue polythene seems to be doing the trick... )

The main draw back I have with the EPDM is that it will come in one big roll, and I imagine will probably weigh the same as an elephant, so shouldering it up the ladder won't be an option...!!!

Thanks in advance,

Dougie.

 

[^woody^]

EPDM will come folded up rather than on a roll. Its heavy though - but I managed a 6x4 sheet up a 2-storey ladder, so not impossible

Both systems should perform more or less the same, but EPDM manufacturers claim a longer life

Unless you can lay felt yourself, then EPDM will be easier to fit.

Search this forum, there are lots of posts on the advantages of each.

 

[noseall]

Its heavy though - but I managed a 6x4 sheet up a 2-storey ladder

Woody.......

 

[bendylow]

looks to me like woody could do with gaining a few pounds.

 

[DaveckJ]

As you suspect and as Woody mentioned a 30 square metre sheet will be a good old weight - if it is a single sheet it will weigh in in excess of 35 kilos I should think!

If it is a single sheet you use and it is folded rather than rolled then be careful unfolding it on the roof if there is a bit of a breeze as you will be unfolding a large sail! Ask me how I found out!

Both systems do not perform the same. Epdm has been scientifically proven - German research - to last many many times longer than bituminous based felt roofs. A properly laid EPDM roof will last in excess of 40 to 50 years. Felt will not and does not last anywhere near that length of time - hence why you are probably having to replace the felt on the roof in the first place.

I have recently been to have look at a EPDM roof that was put on a 120 square meter roof in 1982 (so by my reconning it is 27 years young) and it is still completely water tight and still looks fantastic I thought. Won it for me because since 1989 we have had our felt roof re-done twice. First time it lasted 8 years second time about 10 years - therefore went the EPDM route as I didn't fancy the plastic stuff.

Its not to bad to install once you get cracked on with it.

HTH

DaveJ

 

[^woody^]

I remember the days when we carried proper bags of sand and cement (ie 50kgs) on our shoulders across the yard

I think my abs need a bit more work though

 

[Bloosman]

Thanks guys...timber decking has been repaired and I'm in touch with suppliers of EPDM to see what the options are...

Friend of mine has recently done a new dormer in felt, so I may go down that route and get him to help.

Dougie.