Stcky sealant

[Jim S]

I have an ongoing problem with a 5 year old plastic guttering joint two floors up. It drips. It is in a slight sag which I cannot change without major surgery. First I unclipped the joining clip at both sided, cleaned the rubber seals and refitted it. No better. Next time, I unclipped the joining fitting, and used Unibond roof and gutter sealant in the gap before re-fitting. No joy. Third time I used loads of the sealant in the area where the drip appears to com from, but it still drips.

The sealant is very difficult to work with. I am loath to use water to smooth it, but how else?

[Andrew Gabriel]

Lengths of guttering expand and contract quite a lot each time the sun comes out and goes in. The joins all have expansion gaps to allow the guttering to epxand and contract into them whilst keeping a waterproof seal, if fitted correctly. I suspect this was damaged, but the application of sealant will have wrecked it, and probably the ends of the gutter which go into it, unless you can clean them back up to be smooth shiney plastic on the outside (sealing) surfaces.

You need a new joining piece, and new lengths of guttering if the ends are damaged by the sealant. When assembling, smear the rubber seals with silicone grease designed for pushfit plastic wastepipes so they slide easily in the joining piece. Make sure you allow space for expension (the gutter fittings show how far in to push the guttering).