Please see below some tips & advice on how to best prepare your flat roof, ready to install your Triple Glazed Flat Roof Skylights.
Your decking (only applicable when using an EPDM rubber membrane):
Firstly, & if possible, the direction of run-off from your deck, should be across the shortest length of your skylight, with the shortest run going 'towards' your gutter edge.
If your skylight doesn't run parallel to your gutter edge - when making your kerbs, ensure there is still a fall of 1 in 40 across the shortest run.
Secondly, you should consider having firings or a fall in place to also encourage water run-off 'around' the highest side of the skylight, reducing any standing water on the highest point of flat roof.
Step 1: When installing your joists & or decking (typically 18mm OSB), & planning your openings, bare in mind that the size of your structural opening must be the same as the skylight size ordered.
For example, a 1200mm x 1200mm skylight, will required the same size structural opening.
Step 2: For best results & no joints (only if using the preferred system of EPDM rubber), the membrane should be bonded in one piece.
To achieve this, plan & secure some temporary boarding over the skylight opening - which is safe to walk on.
The top of the temporary boarding should be flush with the top of your decking.
Bonus tip: Draw a diagram & note specifically where the corners of the opening are, ready to cut your EPDM at a later step.
Step 3: Bond your membrane to your decking in one piece, as seen in Laying Your EPDM.
Take care to not glue your EPDM onto your temporary boarding, or 75mm around the perimeter - as this is where your timber frame will secure to your decking.
Step 4: Consulting your sketch from your previous bonus step, cut from each corner of your temporary boarding (plus the 75mm) at a 45 degree angle, towards the centre of the opening.
Step 5: Fold back the 4 pieces of EPDM now cut. You should be able to fold each piece 75mm past the temporary opening.
You may now remove the temporary boarding, taking care not to damage your EPDM.
Congratulations, you now have a seamless finish to your Elevate EPDM flat roof! No joints needed!
You are now ready to follow the steps in the skylight installation guides.
If the skylight frame is fitted before the EPDM:
On occasion, the skylight frame may be fitted before you can lay your EPDM membrane, perhaps a previous contractor & joiner have completed their stage before you (the next tradesman) completes yours.
If this is the case, you can consult Laying your EPDM around obstacles & angles for advice on how best to bond your EPDM around the skylights - along with subsequent flashing & sealingl