Building A Sloping Roof

[annieigma]

Got the concrete tiles, only wanted about 220, but man said if you take all 800 you can have them for £50 the lot. they are secondhand redland 46 i think. next question is, how far can we span with out under support? we were thinking of screwing a beam to the wall, about a mtr up from the existing flat roof, then joists from that to the front of the sun room wall, total distance about 4 mtrs. will this sag? should we lay a plank on the flat roof and put uprights from that? ( flat roof not very flat)
thanks,
annie.

[The Builder]

I can't find any data on the Redland 46 , Annie. Maybe it's long discontinued.

No matter. Just give me the rough size of the tiles.
Also, are they smooth or granular (it affects the pitch... ie the slope)

[annieigma]

Hi builder,
thanks for your reply. i have had another look, they are redland 49, they are rough to the touch. just found the redland site and the spec is there, but no help to me as its the frame construction thats the problem, size of timbers required and spacings etc. any advice much appreciated, and, i don't believe the redland site saying how much a 1000 tiles weigh, does that mean that the house they came off had almost 3 tonnes of tiles on the roof??? about 850 tiles??
thanks for your time,
annie.

[The Builder]

Roughly 3kg each, Annie. So 850 tiles = approx 2.6 tonnes.

First thing ... With your "wallpiece" (beam along the wall) at only 1 metre high, you will only have approx 15 degrees.
Granular tiles need a minimum of 22.5 degrees. Your wallpiece will have to be at least 1.5 metres high.

Can you do that?

Taking rafter sizing from the tables ...... you'll need 50x150 rafters (6"x2") for a clear span.

That can be reduced if a "purlin" is used. That's a big timber that runs at right angles to the rafters... underneath them to support them.

Each end of the purlin would either have to be supported in a wall, or from the structure below (sun room).

Is the sun room Upvc, or is it traditional construction of masonry/timber frame?

[annieigma]

Hi Builder,
thanks for the reply, weight of tiles is scary. sun room built by previous owner, made of brick, don.t actually know if it has two skins, will have to drill a hole tomorrow. also the front is all patio doors, so also bit cautious as to if there is a lintel etc. the roof is going to butt upto existing single floor extension which has same tiles, and i think the fall is only one mtr. but not had any water trouble or tile slip etc. Will investigate further in daylight,
Best regards,
annie.

[annieigma]

Hi builder and everyone,

Can someone give a bit more info please. the sun lounge roof measurement is actually 3 mtr x 3 mtrs. ( 3 mtrs is the actual length of area to be tiled, we measured the existing tiles from wall to end of tile over guttering) the maximum fall can only be 1mtr slope, as it will be joined to the existing sloping roof of the single floor extension which is 5 mtrs long and 3 mtrs out, so when the sun lounge is finished the roof shold look like one long roof of 8 mtrs. what size wall plate and joists are required please.? is a 600 spacing of joist correct? Thank you, work is imminent now the rain has stopped.

[annieigma]

Hi all,
no answers, so thought everyone was watching the football, anyone help with the problem?
thanks, annie and dogsbody ( as He calls Himself)