Rendering costs in Middlesbrough: what changes the size of a job

Access and removal

Scaffold is often a large part of a job. A two-storey gable, a rear wall over a lower roof or a wall reached only through a neighbour's garden needs more of it, for longer. Towers may do for a bungalow.

Removal is the next variable. Hacking off well-bonded pebbledash is slow and creates heavy waste; loose render comes off quickly. A quotation that assumes the old render stays is a different job from one that strips it.

What is found underneath

Repairs found after removal are the most common reason a job grows. Soft or broken bricks, failed pointing, old openings filled with mixed materials and damp brick at the base of a wall all need putting right before new render goes on. Ask how such findings will be reported and agreed before work continues.

System, details and weather

A two-coat sand-and-cement render needs an undercoat of about 10–12mm, left to dry for days, then a finish coat, according to the Mineral Products Association data sheet. A sprayed monocouche goes on in one thick coat; a silicone finish needs a basecoat, primer and thin top coat with waiting times between. Each has a different amount of labour and time on site.

Details add work out of proportion to their area: beads at every corner and reveal, a bell-cast bead above the DPC, sills extended to throw water clear, downpipes and fittings off and back on. External insulation adds boards, fixings, mesh and reworked eaves. Under Approved Document L for dwellings, replacing a render layer is renovation. Renovating more than half of a thermal element, or more than a quarter of the external building envelope, calls for an insulation upgrade where feasible. Settle the measured areas and required improvement with building control before comparing render-only and insulated quotations.

Finally, weather. Render products have minimum temperatures and cannot go on in frost or rain, so winter work can take longer.