Stepped Flashing

[alanthomaswatson]

Folks

I'm looking at putting an extension on my kitchen, which will take the form of a lean to. The back of the house is broadly L-shaped and the extension will make the L into a square.

I have sorted the ridge/pitching plate detail, but I'm a bit confused over the stepped abutment detail to the pitch. Intention is to have a lead soaker and flashing arrangement, and having done some searches of the forums keep seeing mention of cavity trays.

My walls are solid, so I obviously can't install them? Is this an issue?

Grateful for thoughts.

 

[freddiemercurystwin]

If you have solid walls you cannot easily insert a tray, should'nt be an issue with regs unless the inspector is an idiot!.

http://www.leadsheetassociation.org.uk/html/1404.html
http://www.learnatrade.co.uk/AADownloads/CalderGTGLW.pdf page 14

 

[alanthomaswatson]

Building Control? Idiots? Hmm.

Thanks for the note and the links to guides. I've no way of installing a cavity tray but we'll see what BC say!

I'm planning on using the Monier Cambrian slate on a roof pitch of 16 degrees. Anyone know what the recommended method of forming the stepped abutment is?

Is it a flashing, flashing with soakers, single step with cover or single step with secret gutter?

If a secret gutter, how deep are these? The width is on the calder guide, but no depth.

 

[freddiemercurystwin]

Is this an abutment with a vertical wall on the side of the roof rather than at the top of the pitch as per my first link? If so, the depth of the secret gutter will be the depth of the battens ie about 25mm http://www.leadsheetassociation.org.uk/html/1402.html

 

[SurreyRoofingEstimator]

Your best (and easiest) bet at the side abutment with Cambrian's would be to use a Klober GRP secret gutter that goes the same depth of the batten with a cover flashing over, If you look at the Redland Manual (downloadable) it will show you exactly how it goes

 

[justlead1]

Hi. It may be of help? i have a little video of fitting stap flashing http://justlead.co.uk/news/Page-2.html it may well benefit if you are doing it your self. Good Luck