- Manufacturer: A W Hawksley Ltd – Bristol Aeroplane Co.
- Forms: Detached, semi-detached and terraced bungalows
- Built between 1948 -1950
- AKA: Permanent Aluminium Bungalow, BL8D Aluminium Bungalow, Blackburn, Hawksley Aluminium Bungalow BL8 , BL8D, Permanent Aluminium
- Total Built: 55,000
The BL8 Bungalow is an aluminium framed system constructed between 1948 and 1950 and are semi-detached and detached units.
Constructed almost entirely of aluminium, the rust-proof homes have more than outlasted their intended purpose.
Each bungalow usually has three bedrooms, a living room, kitchen and bathroom with toilet. The rooms are generally spacious and all the bedrooms are capable of taking a double bed and often these properties had a decent sized garden at both the front and rear.
A number of different types of long and short-term use prefabricated bungalows were built in Britain following the end of wartime hostilities, and each type incorporated different materials into their design.
The BL8 made good use of the excess stocks of aluminium that had been left over from the war effort, a material that had been previously been used to produce fighter aircraft. The Governments wartime policy encouraged the collection and recycling of many different metals during the war. Anything made of aluminium was sent to the United States where it was smelted and processed into sheet aluminium before being shipped back to the UK to for military aircraft production.
The Hawker Sidley Group was one such aircraft manufacturer who post war, converted their factories and production lines to the the manufacture of housing units and components.
The bungalows were factory constructed in sections of six-foot modules that were delivered on site before being hoisted into position and bolted together, saving many hours of time and reducing the need for skilled labourers which were in short supply at the time.
Despite this, there were still insufficient numbers of workers available to erect the large numbers that the factory was producing so experienced chalet builders were brought in from Norway where no such labour shortage existed, as Norway had remained neutral during the war.
The majority of occupants even today, speak very favourably about these homes, many of which have now been improved further with the application of External Wall Insulation and triple glazing, providing warm and comfortable homes for the occupants.
Due to the anti corrosion properties of aluminium, rust has never been a problem for the main body of this hardy little bungalow. Many examples can still be seen standing proudly today and in remarkably good condition considering their age. As with all property purchases though, a full structural evaluation should be undertaken before purchase as there is no guarantee that all components or fixings remain strong and stable. Corrugated or pressed steel sheeting was used as the roofing material which is subject to corrosion but fortunately not too costly or difficult to replace.
- The framing is a mix of “T”, “C” and “T” sections forming a simple beam and post arrangement.
- The original external walls were built using corrugated aluminium sheeting, lined internally with plasterboard or hardboard and glass fibre insulation was used to insulate the wall cavity. Flat sheets of aluminium cover the gable apex.
- The party wall is of similar construction to the external wall and therefore an application of a suitable noise reduction material would be advantageous.
- The roof is constructed using timber trussed rafters which support lightweight steel roof sheeting.
- The ground floor is concrete and the foundations are of brick atop a concrete strip.
The BL8 construction was not Designated Defective under the Housing Defects Act 1984 or the Housing Act 1985.
Details of the form of construction can be found in Department of the Environment, Housing Development Directive “Temporary and Permanent Aluminium Bungalows: Corrosion” and “Prefabrication – A History of its development in Great Britain” by R.B. White published in 1965 by HMSO. The form of construction is illustrated in Appendix C3.
A later version, the BL8, was a complete change from the B1 and B2 box structures. It was designed for the site assembly of flat panels for external walls and partitions, and was of greater total area (82m² for BL8, 62m² for B1 and B2). The BL8 was designed as detached, but were mainly erected as semi-detached pairs.
A total of over 150,000 temporary houses were manufactured or imported during the period 1945 to 1948, of which about 55,000 were aluminium.
The aluminium bungalow was the most highly prefabricated of the programme, with production concentrated in five large factories. Production of complete bungalows was in four fully finished units, transported to site on special low loaders.
The houses were produced under the direction of the Ministry of Aircraft Production with preparation of sites by the Ministry of Works. The four units making up a bungalow were pushed along sets of rails to their appropriate place on the foundation slab. The jointing between units was via wooden batten placed in vertical channels in the edge of the wall panels. This batten acted like a tongue in matchboarding. The cavity was packed with insulation and closed with cover strips of aluminium. Similar strips protected the roof joints.
- At eaves and base of wall the units were locked by ‘V’ shaped interlocking connector bolts of aluminium through which a pine was driven horizontally.
- The foundations comprised 100mm thick concrete ground bearing slab, with 230mm brick perimeter walls.
- The external wall panels were 83mm thick, aluminium frame members faced with aluminium sheet and internally with plasterboard. The cavity was filled with fibre glass insulation, separated from the external sheeting by waterproof building paper.
- The 50mm internal partitions were built with aluminium frame panels faced on both sides with 6mm plasterboard.
- The concrete floor slab was covered with mastic asphalt flooring tiles.
- The roof comprised aluminium sheeting, lined on the underside with 19mm insulation board supported on aluminium trusses and purlins.