House martin nest dilemma

Hi, I'm new to the site and want to ask a few questions. Question one refers to the fact that in 6-8 wks time I'm going to have a new front door installed. There's a nest in the porch just a foot or two away from the door. This nest is normally taken by house martins. The 6-8 wk lead time takes the installation date to mid-end April. Will this disturb house martins?

My second questions also refers to house martins. I have an old unused stable overgrown with Ivy which I want to convert to a studio. This will require putting on a new but rudimentary roof and doing a bit of plastering etc. Currently, the stable is the summer home of loads of house martins. I don't want to lose them and was thinking about how viable it was to move the nests - that is, literally prise the nests from the beams in the stable, and re-adhere them on the outside of the stable. Would this work? Would they use the nest (it certainly won't be as cosy having a nest on the outside of a stable as the inside)? Would they be put off by building work to put on a new roof? What do you advise?