Hi
Hoping someone can help me!
We are currently having a large side extension and we instructed a main contractor to do this. It was supposed to be finished mid December (14 week project) but has overrun considerably with no reason why, the builders just seem very slow. Currently they are estimating to finish mid February. We have told them it needs to be earlier as we are due to remortgage in February and want to do so with the extension finished. They knew from the beginning we wanted it complete before Christmas and even the week before seemed to think they could still get it finished somehow.
During November/December they started the roof and almost daily left our existing home at risk of damage from rain. Unfortunately we have suffered bad water damage to all the rooms that join the new extension as the builders didn’t ensure it was watertight when they left each night when joining the old roof to new roof.
My husband is good at DIY and spent many evenings/weekends making good the exposed areas the builders left to avoid further damage. We asked our builder to return to site to correct several times but he wasn’t interested and asked my husband to do it.
We are getting another contractor to repair the water damaged areas and we will be deducting this from our main contractors next payment. But we don’t know what to do about the time my husband has spent fixing what the builders should have done. He was on the roof at night in the dark and even had to repair our conservatory roof on Christmas Eve as one of the builders stood on it and bent something which caused more water to come in. We want to deduct an amount of money for my husbands time but don’t know what would be reasonable?
If he hadn’t done the repairs we probably would have had to have moved out as the damage would have destroyed so much of our existing property.
The first night we had a leak water we found water dripping into our then 2 month olds bed while she slept! We moved into the spare room that night.
We are so fed up but don’t know what we can reasonably deduct for the hassle? Any help would be much appreciated! 
Thanks