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Technical Overview

Introduction

The BCIS Notional Rebuilding Cost Matrix calculates the notional rebuilding cost of a residential property given minimal details and is based on the BCIS Rebuilding Cost Models accepted as standard by surveyors and loss adjusters.

The BCIS models cover a wide range of houses (including bungalows), houses converted into flats and purpose built flats, but not all domestic property is covered. Exceptions and exclusions are described below, along with some information on the approach.

Listed or Unusual Properties

Listed buildings and properties that have special or unusual features are not covered by the Matrix. Some listed buildings can require very expensive specialist crafts to reinstate them while other examples may cost little more than an equivalent modern house to rebuild.

Buildings within a conservation area will normally be covered by the models, although any special or unusual features that would need to be recreated cannot be assessed. Buildings with special or unusual features, including architect designed houses are not covered by the BCIS models.

Houses

Houses may be detached, semi-detached or terraced (end of terrace is treated as semi-detached). Bungalows, two, three and some four storey houses are covered. Styles of houses have changed over the years and BCIS has identified five age bands:

1720-1839
1840-1919
1920-1945
1946-1979
1980 to date

Table 1 shows the coverage for age and type but the principle exclusions are as follows:
Bungalows: No models for bungalows prior to 1840.

Four Storey Houses: Only available for 1720-1839.

Flats

BCIS recommends that flats are insured as a block rather than individual flats being insured separately. It is acknowledged that this is not always possible and so the Matrix will provide the rebuilding cost based on individual flats. If the block is to be insured then professional advice should be sought.
Houses Converted into Flats: Models are available for two and three storey houses built between 1840 and 1945 which have subsequently been converted into flats. Table 2 shows the coverage for conversion flats.

Purpose Built Flats: Models are available for low and medium rise (two, three or four storey) blocks of flats built since 1945. Table 3 shows the coverage for purpose built flats.

Size

The main factor affecting rebuilding cost is the size of the property and the BCIS models use floor area to measure size. As the floor area is not normally known, the Matrix uses the number of bedrooms at the property to determine the floor area. Using a combination of BCIS research over the last 30 years and data from over 100,000 surveyor’s reports (where the surveyor has visited the property), the floor area of the property is determined from the number of bedrooms relative to type, style and age.

Quality

Quality is another major factor in the cost of rebuilding houses and flats. The BCIS models have three levels of quality: Basic, Good and Excellent. On average, surveyors class approximately 5% of properties as Basic and 5% as Excellent, although the proportion varies with type, age and size of property. The notional rebuilding cost is based on the BCIS Good quality dwelling.

Construction

The BCIS models are all based on ‘traditional’ construction of brick or stone walls and tile or slate roofs.  Please note that the cost of stone can vary significantly depending on the type of material and construction.
Timber framed houses with brick cladding and pitched roofs have become more popular since 1980. The cost of constructing a single timber framed house in this style is similar to the cost of brick/block construction and the models therefore apply. Timber framed buildings that are also clad in timber are not covered by the models.

Cement rendered block-work is a common form of external wall construction, especially in Scotland. The cost of construction is similar enough to brick wall construction for the models to be applicable.

Garages

An allowance for a typical garage configuration in included in the BCIS Notional Rebuilding Cost Matrix.

Other External Works

A typical allowance for walls, fences, paths, sheds, garages and drives is included by default in the rebuilding cost. However, the extent and nature of these additional items depends on the size, type and location of the property. It should be noted that the extent and cost of external works can vary significantly from nothing up to and beyond the rebuilding cost of the house, especially where extensive or unusual grounds are present.

Updates

BCIS models are completely re-priced each year after which a new Matrix will be provided. Between annual updates, a monthly index figure is provided to allow the rebuilding cost figures to be updated to current prices.

Demolition and Professional Fees

The rebuilding estimates include an allowance for the cost of demolition and removal of debris, support and weatherproofing needed to adjoining structures and architect’s and surveyor’s fees.

Table 1 - House Coverage

Period	Type	Bungalow	Two Storey	Three Storey	Four Storey
1980 to date	Detached	✓	✓	✓	X
1980 to date	Semi-detached	✓	✓	✓	X
1980 to date	Terraced	✓	✓	✓	X
1946 - 1979	Detached	✓	✓	✓	X
1946 - 1979	Semi-detached	✓	✓	✓	X
1946 - 1979	Terraced	✓	✓	✓	X
1920 - 1945	Detached	✓	✓	✓	X
1920 - 1945	Semi-detached	✓	✓	✓	X
1920 - 1945	Terraced	✓	✓	✓	X
1840 - 1919	Detached	✓	✓	✓	X
1840 - 1919	Semi-detached	✓	✓	✓	X
1840 - 1919	Terraced	✓	✓	✓	X
1720 - 1839	Detached	X	✓	✓	✓
1720 - 1839	Semi-detached	X	✓	✓	✓
1720 - 1839	Terraced	X	✓	✓	✓

 

Table 2 - Converted Flat Model Coverage

Period	Type	Two Storey	Three Storey
1920 - 1945	Detached	✓	✓
1920 - 1945	Semi-detached	✓	✓
1920 - 1945	Terraced	✓	✓
1840 - 1919	Detached	✓	✓
1840 - 1919	Semi-detached	✓	✓
1840 - 1919	Terraced	✓	✓

 

Table 3 - Converted Built Flat Model Coverage

Period	Two Storey	Three Storey	Four Storey
1945 to date	✓	✓	✓

 

PDF's of the BCIS Cost Matrix Technical Specification and details of the House Rebuilding Cost Index for updating are also available.