Side return extension drawings in Hillingdon

Directions and designations that touch a Hillingdon side return

The council publishes 150 Article 4 directions, covering 150 mapped areas. An Article 4 direction removes permitted development that would otherwise apply, so a side extension that looks permitted on paper can need an application on your road. We look up the direction for your address and say so in writing.

There are also 731 tree preservation orders on the council's register. A protected tree in a neighbour's garden can sit close enough to a side passage to affect foundations and the construction route, and a tree in your own garden is a constraint on the whole plan.

Add 33 conservation areas, where national permitted development gives nothing for side extensions: No side extensions under PD on article 2(3) land (conservation areas etc.). Historic England lists 436 entries in the borough, and Green Belt covers 42 per cent of it.

Hillingdon's householder decisions in numbers

Hillingdon decided 1,147 householder applications in the latest twelve months, and granted 90.2 per cent. 94.3 per cent were decided inside eight weeks or an agreed extension.

On larger home extension prior approvals the council granted 29 and refused 13. Those figures describe the borough, not your application, and we use them only to plan the timetable.

Where a side extension is clearly within the limit, which is Side extension: single storey, max 4 m high, max half the width of the original house, a lawful development certificate in Hillingdon gives you proof for a later sale.

Boundaries, glass and construction in a Hillingdon side return

On a semi the new wall rises beside a neighbour's flank, and building it on the line needs: Line-of-junction (new wall) notice at least 1 month before work. Work that cuts into a shared structure needs: Party structure notice at least 2 months before work.

Glazing is limited by Approved Document L: Windows, roof windows, rooflights and doors in an extension should not exceed 25% of the extension floor area plus the area of openings removed or covered. The same document sets U-values for new elements: 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 in Hillingdon pick these up.

Hillingdon's application fee for householder work is £548. The borough's levy appears as £160.43/m² (Residential dwelling houses C3, borough-wide), and we note any liability in the handover pack.

The practical sequence in Hillingdon starts with the tree and Article 4 lookups, then the survey. If a protected tree stands within reach of the side passage, we ask for an arboricultural opinion before foundations are drawn, and we say so in the quote so it is not a surprise later. Where there is a conifer hedge or a mature garden tree on the neighbour's side, we draw its likely root zone on the plan, because an officer will look for it. With the constraints answered, the drawings themselves go quickly, and the application reads as a considered one.

What the Hillingdon drawings include

Existing and proposed plans, elevations and sections, with location and block plans, for £745 fixed. Every sheet passes a second chartered technologist before Hillingdon sees it, and any changes the officer requests are redrawn free.

If you want to open the back of the house as well, see rear extension drawings in Hillingdon, or the borough overview at architectural drawings in Hillingdon.

A downstairs shower room or a boot room beside the back door fits well in a side return. If you want either, we place it on the plan with the drainage falls and the ventilation in mind, so building control has what it needs without a second round of drawings.