Loft conversion drawings in Merton

Why completeness matters in Merton

The latest figures show Merton deciding 85.2 per cent of householder applications within eight weeks or an agreed extension. An application that arrives with a missing drawing, a wrong scale or an absent form is not validated, and the clock does not start. We check every sheet against the council's validation list before submission.

That is why our independent check is a separate person from the drafter. A second technologist reads the set as a validation officer would, and a senior review signs it off before it goes to the Planning Portal.

Heritage and houses in Merton

Merton has 28 conservation areas, and inside one a roof enlargement is not permitted development. Historic England lists 243 entries, among them 3 at Grade I and 11 at Grade II*. A listed house needs listed building consent for roof changes.

60.4 per cent of Merton households live in a house or bungalow, and 55.6 per cent own their home. House owners can use permitted development where no designation applies. Flat owners cannot, because the roof right covers houses, and usually need the freeholder's agreement as well.

We check protected trees, flood risk and earlier planning history at the same time, because a loft that is straightforward on paper can still be held up by a condition on an older approval for the same house.

Surveying a Merton roof and fixing the stair

Our survey records the roof, chimney, party walls and floors below on one datum. From it we place the stair, which often decides the shape of the loft. Building regulations allow lofts a concession: 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).

A new storey needs a protected escape route, and the roof must meet the insulation standard for new elements. We show both in the section and carry them into our building regulations drawings in Merton.

Once the stair and structure are fixed, we price the options side by side on the same survey. A rooflight scheme, a rear dormer and a larger change each add a different amount of floor area, so you can weigh the extra room against the work each asks of the council and of the builder.

Permitted development or planning permission for a Merton loft

A house that is not listed and sits outside a conservation area may qualify for permitted development if the roof stays within the volume, below the ridge and clear of the front slope. A Lawful Development Certificate in Merton confirms it in writing.

Otherwise a householder application is needed, drawn as in our planning drawings in Merton. The free constraints check tells you which route you are on.

Where a permitted limit is only just met, we show the measurement on the sheet. The eaves rule, for example, reads: Original eaves maintained; enlargement set at least 0.2 m from the eaves measured up the roof slope, so far as practicable (not required for hip-to-gable or roofs joining a rear/side extension). Showing the figure lets a council officer or a later buyer see why the work is lawful.

Merton's householder decisions in numbers

Merton decided 759 householder applications in its latest published year, granting 92.9 per cent. Its minor applications were slower still: 82 per cent were decided in time.

These figures cover all householder and minor work and are no forecast for a loft. They are why we advise a realistic timetable, not a tight one.

What the Merton loft set includes and costs

You receive existing and proposed floor plans, the stair, the roof section and every elevation, with the location and block plans. Loft conversion drawings start at £695, VAT included, and the fee is fixed before you commit.

If Merton asks for changes, we redraw at no charge until approval.

Nearby boroughs and related drawings

For a rear box, see dormer loft conversion drawings in Merton. The borough overview is at architectural drawings in Merton. Next door, compare loft conversion drawings in Kingston upon Thames, which has a rule for piggyback roofs, or Lambeth.