dormer in lead or felt?

bobcar

Hi there

I am currently having my loft converted and the agreement with the builder is for the dormer to be finished in lead on top and at the sides.

The builder has suggested to me that he doesnt think that it is a good idea to use lead for the top as it is completely flat and will contract and expand in the sun, He has advised me to use lead only for the sides and finishing and to use 2 layers of mineral felt for the roof top does any one out there think he is correct.

Thanks

Rob

Wookey

No, use lead, it will last an awful lot longer, if the dormer is any width at all there should be battens added to it that will have the lead rolled over them, these will help breakup any movement in the lead.

iamcornholio

Lead can be used on the top - its just a case of fitting it properly with rolled joints.

I don't know what your builder is thinking about, but even felt flat roofs are not flat

Felt or lead? Well, £1000 for access and replacement of felt every 10-15 years, or possibly sooner, or a minimum of 80 years maintenance free?

The builder has priced for lead, make him use it. And make sure a qualified/experienced plumber does the work too, as its a specialist bit of work to do properly

bobcar

Hi wookey

Thanks for the super quick reply

there are in fact two dormers with a gap in between them each dormer measures aprox 1.5 m2

I specifically wanted them in lead because I have had problems with felt in the past and believe lead to be very long lasting so to reiterate what you have already said there is no reason for me to not go ahead and use lead?

bobcar

Hi iamcornholio

Thanks for your reply

I am now more determined than ever that it will be constructed in lead.

Wookey

http://www.builderbill-diy-help.com/lead-roofing.html

Couple of photos there that show the batten that the lead should be rolled over, typically something like cut stair handrail.

bobcar

HI Wookey

Thanks for the link to the photos of the leadwork it looks really impressive I will be speaking to my builder in the morning and using the information you and iamcornholio have kindly given me to make sure the work is done in lead and also that it is done in the correct way

Thanks again

Rob

ormus

It is not without some drawbacks though.

• While being fairly compact, to state the obvious, lead is very heavy.
• Meaning that it needs a stronger roof framing structure to support it.
• It is hard to transport and more often than not it needs mechanical lifting equipment to get it into position.
• As a sheet roofing material it is very expensive compared to other roofing materials. Less so for flashings. Custom made flashings for other metal roofs are expensive also.

needs skilled manpower to install correctly, and that isnt cheap either.