Class Q Agricultural Conversion

D Hall Plant Hire & Groundworks undertook a Class Q permitted development conversion of a disused agricultural barn (approximately 185 square meters) into 3 residential properties in Liskeard, Cornwall. Class Q is a form of permitted development allowing for the conversion of agricultural buildings to residential use for up to a maximum of 5 dwellings. The client had pre-completed internal fittings removal and floor lowering work before our involvement.

The structural work included concrete wall removal from east and west gables, concrete stanchion cutting and retention, perimeter foundation breaking and removal, and foundation digging for internal walls. We installed comprehensive drainage infrastructure for all three properties with inspection chambers, including a 12-person sewage treatment plant at depths exceeding 4 meters with concrete encasing and ring installation. All ducting for electricity, water, and sewage systems was installed along with three radon sumps and associated pipework.

The floor works comprised a 50mm concrete blinding layer, radon membrane installation using RIW blackjack and Visqueen tanking membranes, A252 reinforcing mesh with L-bars, and 150mm of C40 concrete for the new floor slab. We completed perimeter upstand shuttering and concrete casting, and excavated and trimmed one barn side to improve site access for subsequent trades. The project was completed using a 13-ton excavator and 9-ton dumper with full CDM compliant welfare facilities.