After inspecting the roof of my new house, what I first thought was just paint, is actually a hard coating that has been applied to all the tiles, probably 30 years ago or so.

It has bonded so strongly to the concrete tiles that removal also removes the top layer of the tiles themselves. The overall problem is that the coating has cracked and allowed a huge amount of moss to grow on the roof.

The only options I have are to clean and re-apply a similar coating to achieve an acceptable finish, however, given that the roof is now 80+ years old, I have decided to bite the bullet and replace it, though replace with a clay plain tile, rather than the original concrete.

The questions I have are as follows:

1. There are many specifications for new roofs, and many of them run as follows, from the inside:

a. ply
b. rafter
c. Insulation
d. Ply
e. vapour permeable membrane
f. baton
g. tile

I am wondering what the best option to ask for with regards to both inner and outer ply, membrane and what insulation to opt for.

2. What are the best ventilation options for this roof?

The roof is simple; 3 sides, no gables or flat roof parts.

advice is appreciated.

You do not need the outer layer of ply for a start so that can be discounted.

You seem to be saying that you have sloping ceilings and would therefore have plasterboard, rafter, underlay, batten then tile

Insulation can be placed in various positions in this instance, below the rafter and between, just between, between and over or just over (the last two options will of course raise the barge and soffitt levels. You can also use an insulated felt called TLX-Gold along with other insulation to minimise thickness

When you have the roof done your local building control office will have to be notified and they will tell you what insulation they would want to see so a certificate is issued (though of you employ a roofer who is part of The Competent Roofer scheme they will do this for you)

If you are replacing interlocking tiles with plains, you also need to establish whether the pitch is suitable, i.e. 35 degrees or steeper.

Reading your post suggests that you are replacing concrete plains, yes?

80 year old concretes?

I'd go with e, f, g - no need for any specific ventilation then

Wow, they must be a sory state.

re-roofed a few semis near me last year, used a lovely single camber clay tile from marley called Hawkins, colour was fired sienna. So nice I thought I'd do my own roof ing them

Cost will really depend on your insulation choices, mine was a cold roof before, eaves vented and ceiling joists insulated in between and over.

One thing you might want to think about is replacing your fascias, soffits and guttering, makes sense to do so while a scaffold is up and the tiles are off the roof.

Fired sienna job



Uploaded with ImageShack.us

Nice tiles but why the dodgy bond going into the hips? Standard fare is to use full tiles at the hips then run the cut up the middle of the run.

Why was it done like that??

I don't really know what you mean, this was how I was taught to do it at college all those years ago?

On the left leading hip you have barely an inch of lap.

You should always start at the hips with the the bond then work into the roof.

Also tile-n-halves tend not to work on a 'gaining' hip because eventually you will need a tile bigger than a tile-n-half and this is where straight nick joints appear.

When we reach the point of needing more than atile and half, we start to cut two singles down on each course until it reduces back down.

You cant always start tiling from the hip, if at the other end of the roof theres another hip?

And theres more than an inch lap mate, minimum we go is 50mm and then we start to double cut as above.

Sorry fella but I disagree. If you do it that way you're going to have the tiles out of line on nigh on every course, the full length of the roof. Then tile and half and cuts up the middle somewhere. Not a bit of me.