Hip-to-gable loft conversion drawings in Merton

Detached, semi and terrace: the market here

Merton's housing spans a wide range. The average detached house sells for £2,338,085, a semi for £954,064, and a terrace for £686,591. On the most expensive roads a gable is a design problem as much as a technical one.

On a semi-detached house the national volume rule reads: 40 m³ (terrace house) / 50 m³ (any other house) additional roof volume. Our drawings tabulate the roof volume before and after, so you can see whether you are inside the allowance or heading for a planning application.

Drawing for the top end of that range means more attention to materials. A gable in matching clay tile, with the same eaves and verge detail as the original roof, reads as part of the house. We show those details at a larger scale so the council and your builder are working from the same picture.

Designations that can switch the right off

Merton lists 28 conservation areas, and Wimbledon's are the best known. Historic England records 243 listed entries in the borough. Inside a conservation area, the Class B roof right does not apply, and a listed house needs its own consent in every case.

We check these before any fee is agreed, using the council's maps, and report the result in plain terms. Often the answer for a house just outside a conservation area boundary is better than owners expect, and the reverse is just as true.

Timing: Merton's decision speed

Merton decided 759 householder applications in its latest year and granted 92.9 per cent of them. Only 85.2 per cent were decided within the statutory period, so a decision can arrive after the target date. Build that margin into your builder's start date.

The same dataset records 22 larger home extension prior approvals granted against 80 refused, a reminder that Merton looks closely at schemes that lean on national rights. If your gable fits the rights outright, a Lawful Development Certificate in Merton is the record to hold; otherwise our planning drawings in Merton support the application.

Headroom, fire and the narrow Merton stair

Adding a storey asks that the stair meets Approved Document K, which allows this reduction: Loft conversions where 2.0 m cannot be achieved: 1.9 m at the centre of the stair, 1.8 m at the side (half width). We prove the line on a section through the stairwell, not on a plan that hides it.

Our building regulations drawings in Merton then carry the structural and fire details, including the protected route down to the front door, so building control can approve a single coherent set.

If the stair cannot reach the required height in its present position, we test alternatives: turning the flight, moving the landing, or taking space from a bedroom below. Each is drawn as a short option so you can choose with the trade-offs in view, rather than discovering them on site.

Neighbours, surveys and the next step

A new gable wall often sits on the party line, so a party wall notice is normally part of the programme. We flag it when we first see the roof.

Send us the address and a photograph of the hipped side. We run the check for free and quote a fixed fee, VAT included; no standard price exists, since each roof differs. If you also want a rear dormer, see loft conversion drawings in Merton, or read the service overview at hip-to-gable loft conversion drawings.

If a rear addition already exists, we survey how its roof joins the main one, because that junction decides how the new gable can be built.