Its nice to know some people read our blog posts and then give us a call to find out more… last week I took a call from a contractor trying to interpret an architect’s design. This is always a problem as almost always when DDA design is left to a contractor to sort out they get it wrong, this is most often the case with accessible toilets where the big box fill of handles and rails seems to cause a meltdown in instruction reading. And so it is with tactile paving, and architects note on a drawing and specification saying “install tactile blister paving studs” doesn’t help a contractor very much at all.
So the contractor calls us and asks how far apart blister studs should be, they were gong to use individual tactile blister studs like these [we just googled this we’re not recommending them, but it is a nice product!]. And the answer is… we didn’t know, but we did undertake to help by finding out as it would be useful to know. The answer which we found in the Department of Transport Guide to Tactile Paving [yes, really there is an 85 page guidance note on this] is 67mm apart. See drawing below. Importantly the layout of these should be square and not offset, offset studs – see drawing below – being used to warn of platform edges.
And then, the kicker. We asked the contractor where these were being installed and he said at he top and bottom of a flight of steps. Nooooo, blister studs are used at road crossings and cordurys are used at the top and bottom of the steps, that firm that manufacturers the nice studs above also does a neat line in corduroys [not trousers!]. So we sent the contractor back to the architect, what happened next we don’t know but I suspect there was a “but it looks nice” conversation followed by a new instruction and DDA compliance. And for completeness, cordury pavings need to be set 400mm back from the top and bottom of steps, each corduroy should be at 50mm centres, be 20mm wide and 6mm high, depending on the situation they need to be 400mm to 800mm deep.
image exfordy via flickr