SAP calculations in Newham

A large borough with many households

Newham has a population of 376,542 and 115,507 households, and only 30.8 per cent are owner-occupied. Houses account for 47.1 per cent of households. A terraced house averaged £458,668 in the latest Land Registry figures and a flat £325,381.

At those prices an owner will not pay for energy work that the design does not need. At the lower values here, the best help we can give is to tell you early, in writing and in plain language, whether your extension passes without a calculation or whether a calculation lets you keep a feature you want.

Extensions in Newham: limits first, calculation second

The first route is the one most terraces use. For new elements in existing homes the limits are: 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.

The second check is the area of glass. The rule states: 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. A kitchen at the back with full-width doors can pass or fail on this line, so we count it before anyone commits to a design, and we say plainly where a small trim to the glass avoids a calculation altogether. We measure the floor area of the extension and the area of every opening, then show you the ratio on one page.

If it fails, the document gives another way: Alternative routes: area-weighted U-value (para 10.9) or a SAP calculation against a notional extension (para 10.10). Our rear extension drawings in Newham are drawn with that decision made.

Prior approval and conservation in Newham

Newham sits in band 3, at £30.3 per square metre as indexed for the current year. The Mayoral levy applies to larger extensions and new floor area.

Larger extensions under prior approval were refused more often than granted. For a deep rear addition here, a full householder application gives the council a fuller picture, and the energy work can then follow the plans it accepts. The council granted 6 and refused 23 in the latest year. There are 9 conservation areas, 125 list entries and a Green Belt share of 2 per cent. Fewer heritage constraints leave more freedom to design the building envelope to a good energy standard.

Decisions and new homes

Newham decided 388 householder applications in the latest year, granting 86.9 per cent, and 97.2 per cent were decided in time. These are householder figures and do not cover new dwellings.

For a new home or a conversion into new dwellings, the method is: For new dwellings AD L 2026 names two methods: the Home Energy Model (HEM) and SAP; validity dates are in the Notice of Approval. An energy performance certificate follows on completion: An energy performance certificate is required on construction of a new dwelling. Our flat conversion drawings in Newham cover that type of project.

Where to look next

The wider view is architectural drawings in Newham. To compare neighbours, see SAP calculations in Redbridge and SAP calculations in Tower Hamlets. The plans that support the energy case are the building regulations drawings in Newham.