Yes its not the weight its the stresses if somebody actually swings. I guess
you could just put a mattress underneath and wait for it to collapse!
Brian

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"dennis@home" wrote in message
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On 03/07/2019 20:14, Sus wrote:
I have a simple square pergola in my backyard. It's made of 6" x 6" beams
that are lap jointed. I want to hang 2 swings on each of the two beams.
Is
there a weight restriction given they have lap joints? the swings would
be
wooden and be able to hold an adult.

It depends on how long the lap joints are, what is holding them together
and if the lap is vertical or horizontal.