Skylark 250 floor sections with spans >5.4m?

Hi all!

My question is this: is there a reasonable approach for achieving a clear span of ~6.2m (6.8m on the outside) using a modified Skylark 250 floor block?

Background: I’m exploring using Skylark for a project that is essentially rebuilding a house on top of an existing basement foundation. Using the existing concrete walls fixes the clear span distance at ~6.2m between load bearing walls, which means I need floor blocks that are ~800mm longer than the L size.

My first two thoughts are to a) increase the block height or b) double (triple? more?) up the web elements to achieve the necessary stiffness. Before I proceed further with either approach, I’m curious to know whether there are things I haven’t considered that might make this a bad idea.

Hi @PKL,
both your ideas are sensible to me and definitively worth exploring.
I feel a) is more straightforward, while b) requires more attention to the detailing. However, in principle they would both achieving the same outcome.

Another possibility that comes to my mind is reducing the beams width. For example, the standard cassette is 600 mm wide, but you could make it say 400 mm. The capacity/stiffness of such a beam will be very similar, but the load acting on it would be 2/3 (in case of 400 mm). In other words, you will end up with more beams making up your floor.
This might be perhaps an easier modification of the standard blocks at “block level”. The drawback is that you need to modify all the other blocks (e.g. roof, walls, verges) to have the same width.

Hope it helps. Please keep us updated on how it goes, this is quite an interesting design scenario.


Hi Gabriele,

Thanks for getting back to me so quickly. It’s still very early in the qualification process for me, and I’m glad to see a few different ways forward for the most significant obstacle I’ve encountered so far. I’ll spend some time working on it and report back if anything comes of it. :smile:

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