Project description
I have a timber raised bed in my back garden, four metres long and ninety centimetres wide, and I want a low cold frame built over it for early greens and seedlings. Low is deliberate: I do not want a walk-in structure, just a lid I can reach across from either side. The frame can be treated timber or galvanised steel profile, and I am happy to take your advice on that, but please tell me which will last longer in a damp climate and why you think so.
The top should be two hinged lids glazed with twin-wall polycarbonate, roughly two metres each, so that I can open one half and work on the plants without stripping the whole cover off. One thing is not negotiable: each lid must lock in the open position, either on gas struts or on props with a proper catch. My old home-made frame dropped its lid on my hands in a gust of wind and snapped a whole row of seedlings, and I am not going through that again.
Ventilation is the other must. On a bright day the air under the glazing climbs to killing temperatures within minutes, and there is nobody at home to open it. So one lid gets an automatic wax-piston opener that lifts it on its own, with no electricity involved; the second one stays manual. I also want weather stripping around the rim against cold night draughts, and end panels I can take off completely for the summer.
What I am asking for:
— a site visit, exact measurements and a materials list with prices;
— a frame seated on the bed and anchored to the ground so that wind cannot lift it;
— two hinged polycarbonate lids with hinges and reliable open-position locks;
— an automatic vent opener fitted and adjusted to the right temperature;
— seals around the perimeter and removable end panels;
— assembly on site, offcuts taken away and a short care sheet.
Timing: it has to be standing and working by the start of April. The budget is open to discussion, but please quote materials and labour separately.
The top should be two hinged lids glazed with twin-wall polycarbonate, roughly two metres each, so that I can open one half and work on the plants without stripping the whole cover off. One thing is not negotiable: each lid must lock in the open position, either on gas struts or on props with a proper catch. My old home-made frame dropped its lid on my hands in a gust of wind and snapped a whole row of seedlings, and I am not going through that again.
Ventilation is the other must. On a bright day the air under the glazing climbs to killing temperatures within minutes, and there is nobody at home to open it. So one lid gets an automatic wax-piston opener that lifts it on its own, with no electricity involved; the second one stays manual. I also want weather stripping around the rim against cold night draughts, and end panels I can take off completely for the summer.
What I am asking for:
— a site visit, exact measurements and a materials list with prices;
— a frame seated on the bed and anchored to the ground so that wind cannot lift it;
— two hinged polycarbonate lids with hinges and reliable open-position locks;
— an automatic vent opener fitted and adjusted to the right temperature;
— seals around the perimeter and removable end panels;
— assembly on site, offcuts taken away and a short care sheet.
Timing: it has to be standing and working by the start of April. The budget is open to discussion, but please quote materials and labour separately.
Other / Miscellaneous Cash, Bank transfer
