Velux loft conversion drawings in Merton

Rooflights under permitted development in a borough of houses

Merton is a borough of houses: 60.4 per cent of households live in one, so most clients have the right to alter the roof. The national limit is the starting point: Roof alterations (e.g. rooflights) may not protrude more than 0.15 m beyond the roof plane. A Velux scheme builds nothing outward, so it is one of the quickest loft routes to prove lawful.

Rights are not universal. Merton has 28 conservation areas and 243 listed building entries, and a house inside one of the areas, or listed itself, needs a different approach. We check the address before we quote a route.

Side-slope windows have their own condition: Side roof-slope windows obscure-glazed and non-opening below 1.7 m. On a semi-detached or end-of-terrace house that decides whether a side unit is useful or not.

Character, small sites and what the guidance says

Merton's householder-relevant documents include the Borough Character Study SPD and the Small sites toolkit SPD, alongside the Basement and subterranean SPD. None of them gave us a rooflight rule with a page reference, so we do not invent one. We draw to the national limit and to the character of the street, and the covering note names the Local Plan, adopted in 2,024, as the policy basis.

Merton also carries an Article 4 direction for houses in multiple occupation, which matters if a new loft bedroom is part of a plan to let rooms to sharers. We describe the room on the plans as part of the existing household, which is the honest description for most of our clients.

The numbers behind a Merton loft room

A terraced house here averages about £686,591 in the latest index. The extra bedroom is worth building where the roof has the height, and the stair decides that: 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 draw the stair on a measured section of your own house, with at least two positions compared. If the ridge is too low, a dormer loft conversion in Merton is the alternative, and loft conversion drawings in Merton sets out the full range.

The escape and fire details follow: Escape window: unobstructed openable area at least 0.33 m², at least 450 mm high and 450 mm wide, bottom of opening no more than 1100 mm above floor. And for energy: New elements in existing dwellings, limiting U-values W/(m²·K): roof 0.15, wall 0.18, floor 0.18, windows 1.4 (or WER Band B), doors 1.4. Our building regulations drawings carry both forward.

Using the waiting time well

A slow decision is not wasted if the building work is prepared in parallel. While the council considers the rooflights, we can issue the construction details, so that your builder and structural engineer price the same drawings and the building control submission goes in the day the decision arrives.

We also use the gap to settle the smaller choices that cause delays on site: which rooflight product, where the stair lands, how the new floor is insulated for sound as well as heat. Settling them on paper costs far less than changing them once the roof has been opened, and it gives the builder a fixed scope to quote against.

Fee, checking and neighbouring councils

The fee is £695 including VAT, fixed in advance. Each sheet is checked by a second MCIAT chartered technologist, and we redraw for the council's comments without charge.

More on the borough is under architectural drawings in Merton. Nearby, Sutton, Wandsworth and Kingston upon Thames follow their own guidance.