The rising costs of transport and raw materials and a shortage of tradesmen is pushing up the costs of home improvements, according to the Royal Institute of Chartered Surveyors.

Its Building Cost Information Service’s updated Property Makeover Price Guide gives homeowners an accurate guide to what they should expect to pay for home improvements. It has found the average cost of improvement work has risen by 20 per cent over the past two years.

With half of the estimated one million British-based Poles having already left the UK, competition for labour is pushing up costs.

The upward trend in oil prices is continuing to fuel the rising cost of transport.

Global demand for raw materials remains at an all-time high.

This is no more evident than in the various trades where the cost of materials has pushed up the overall costs. For example, roofing costs have risen by 26 per cent, plumbing and electrical work by 22 per cent and painting has risen by 17 per cent, all outstripping inflation over the past two years.

The guide also allows readers to adjust the figures for their particular location. For example, a 3m by 3m single-storey extension will cost approximately £23,940 in Greater London; in comparison it would cost £19,320 in the North West.

The guide not only provides advice on prices but also on the do’s and don’ts of employing a contractor and organising building work, planning permission and building regulations.

It covers everything from inspecting blocked drains to doing a loft conversion.

EXAMPLES

1 Repairing windows in poor decorative order (both sides of an average window size from 600 by 900mm to 1500 by 1200mm)

Was £75 - £280

Now £88 - £330, a 17 per cent rise

2 Repairing overflowing gutters

Clean out gutters, outlets for whole house (dependent on house size)

Was £160 – £460

Now £205 - £580, a 27 per cent rise

Plus realigning PVCu gutters

Was £340 - £1260

Now £430 - £1590, a 26 per cent rise

3 Restoring a wall affected by damp penetrating through an external wall and plaster wall

Was £72 - £115 ( area 1m to 5m2)

Now £83 - £135, a 16 per cent rise

4. Resecure roof tiles/slates

One tile was £220 now £280

Six tiles was £245 now £310, up to 17 per cent rise

5 Replacing cracked brickwork using scaffolding (2m length of crack at a high level)

Was £205 - £330

Now £240 - £380, a 16 per cent rise

6 6m by 5m loft conversion with two Velux windows

Was from £14,000

Now from £17,000, 21 per cent rise

7 Adding double glazing (PVCu sash window – approximate window size 600 by 900mm – 1200 by 1200mm)

Was £850 -£1,580

Now £1,040 - £1,930, a 22 per cent rise

8 4m by 4m single-storey house extension with one window

Was £18,500 - £23,000

Now £22,500 - £28,000, 22 per cent rise

9 Basement conversions (floor size 3m by 5m)

Was £8,000

Now £10,000, a 25 per cent rise

10 Adding a 4m by 4m conservatory

Was £15,000 - £19,000

Now £18,500 - £23,000, a 22 per cent rise

n The Property Makeover Price Guide: Organising and Budgeting for Home Improvers & Developers, £17.99 can be ordered online at www.bcis.co.uk or by calling 0870 333 1600 (select option 2 for BCIS sales and quote item code 17381). Also available in bookshops.