Expert: Richard Taylor, AIA - 4/10/2009

Question
Hello Richard, On my house I have a 1st floor 24'x12' addition, with a rubber roof that was just installed. There are two posts at the two corners away from the house which my carpenter installed before the rubber was installed. They are for the railings. I want to install  modular decking so that I can remove it for cleaning and repairs if needed. Is there any reason that modular sections would create more pressure and potential damage to the rubber than sleepers would? I know that the carpenter will have to install slippers under all wood touching the rubber. Have you ever designed a modular deck on a rubber roof? I haven't had luck finding a carpenter who has experience with this so I want to be involved in the design process and make sure it's designed and built the best way possible.  Thanks for any tips.

Answer
Laurie - thanks for your question!

You're 99% of the way there, everything you've written is exactly right!  All that you need to do is make the deck modules light enough that you can lift them up when needed for cleaning.

The modules won't create any more pressure; the loading should be exactly the same as it would be with sleepers.

If you can attach the slippers under each of the sleepers without exposed fasteners, that's best.  Otherwise be sure the nailheads are flat and flush with the rubber slippers.

Keep up the good work - you're doing it correctly!

Hope this helps,

Richard Taylor, AIA
www.rtastudio.com
www.rtaplans.com