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Identification Construction Type Identification - Reading, Berks

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I was wondering if I could get some help in identifying the construction type of a property that I have recently put an offer on - rightmove link here:  

I am a first-time buyer so fairly new to all this, but when our prospective mortgage lender conducted their valuation they noted it was a non-standard construction property and have asked questions about what specific type of construction it was before they could make a lending decision. 

Having talked to the vendors, and having looked up some information about the local area, I think it's some form of bison concrete construction; although I may be way off.

If anyone is able to help, that would be much appreciated. Also, if anyone is able to let me know if there's anything I should be aware of, or any information I should give to the lender, with this type of construction that would be helpful too.

Thanks in advance.

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2 Answers

Hello Tommy and warmest of welcomes to our forum.

I can confirm straight away that your property is indeed of Bison large panel construction.

The Bison system is based upon large storey height precast reinforced concrete panels and usually in-situ concrete joints at the junctions of the panels and floor units. The in-situ joints contain steel reinforcements which tie the panels together and provide strength & continuity to the structure.

The first Bison system dwellings were erected in 1963 and over the years a number of systems have evolved, these being the Bison Wall Frame, Bison Preferred Dimension, Bison Trimline an finally the Bison Crosswall which is what your property appears to be.

Bison's first housing contracts using their own complete systems started in 1963 with a scheme at Kidderminster. Prior to this, Concrete Ltd, the manufacturers of Bison concrete products, had produced concrete components such as floor units, columns and beams, for incorporation into other buildings.

Here's some technical spec.


  • 2-storey semi-detached and terraced houses.
  • Shallow pitch gable roof covered with concrete tiles, mono pitch roof covered with aluminium sheets or flat roof covered with bituminous felt.
  • External walls are either of brick throughout or with front and rear walls of horizontal timber boarding.
  • Guidance on inspection and assessment of reinforced concrete durability is given in BRE Building Research Establishment publications:
    Corrosion of steel in concrete (BRE Digest 444, Pts 1–3)
    Repair and maintenance of reinforced concrete (BR 254)
    Carbonation depths in structural-quality concrete (BR 19)
    The Bison system was also used for low and high rise flats.


2021 04 22 21h14 12

Substructure: Concrete strip footings. Concrete under- building. DPC.

External walls: Front and rear walls of brick [1], cavity, and PC blocks [2]. Brick-on edge copings.
Flank wall of brick [3], 2" cavity, 4" storey height PC panels [4] with cast-in loop reinforcement and vertical lacing bars. Panels located and levelled on levelling bolts housed in panel base pockets. Infill concrete between panels [5]. PC wall capping [6]. Insulating blockwork [7].

Separating wall: 7" storey height PC panels with cast- in loop reinforcement and vertical lacing bars and infill concrete; wall ties project from ends of wall on front and rear elevations. Panels used for projecting cross wall thickened to 10" at external wall.

Partitions: Timber stud lined with plasterboard.

First floor: Screeded 9 1/2" Bison Widespan M hollow cored PC floor slabs [8], 1/2" compressed polystyrene insulation [9]. Front and rear slabs have wall ties projecting from edges to tie in with blocks.

Ground floor: Concrete.

Ceilings: Plasterboard.
Roof: 9 1/2" Bison Widespan M PC floor slabs, insulation to falls [10] and bituminous felt.


Shallow pitch timber roof covered with concrete tiles. PC gable apex panels.
Mono-pitch roof of RC spandrel, timber trusses and aluminium sheets.
Cross walls of plasterboard on timber framing with or without insulation.
External walls with foam insulation in cavity.
Front and rear walls of timber frame infill panels clad with horizontal timber boarding.


This system was produced in the late 1960s for low­ and medium-rise construction. The system comprises of solid precast reinforced concrete panels as the loadbearing walls, which run from the front to the back of the dwellings. These walls become the flank walls and also the party walls between dwellings. Wide precast reinforced concrete floor units span at right angles to the cross walls, forming the floors and flat roofs. The flank walls have wall tics cast into their outer faces to enable a brickwork outer leaf to close the structure.

Party walls are fair faced on both sides. Front and rear facades usually consist of lightweight timber­ framed panels or cavity-wall masonry infill.

The method of erecting the loadbearing panels is similar to that for Bison Wall Frame construction.

bison crosswall

Here's a link to Reading Councils housing stock list, which lists the road of your property. It is in XLSX format, so let me know if you have trouble opening it.

Finally, you may find that your lender may be a little wary once they hear the name Bison or large panel system. This is mainly due to a number of defects that have been found in certain large panel, high rise constructions, where insufficient load support and a variety of other issues have occurred. This has caused some lenders to cautious when considering this type of system, even though your prospective property is a low rise dwelling. This doesn't happen with all lenders though but don't be surprised if your lender requests a full structural survey before making a decision.

Let me know how you get on for the benefit of other prospective buyers of similar properties.

Best regards



tommys tommys Topic starter 23 April 2021 5:10 PM

Hi Marc,

Thank you so much for such a detailed response - and a very quick one too!

Our current prospective lender seems wary and we're unsure whether we will win them over. It probably doesn't help that we're looking for a high LTV mortgage.

So we're preparing to start a new application with another lender and have gotten in contact first to see whether they would even consider this type of construction. The current owners got a mortgage with a major high street lender only 2 years ago so keeping hopeful that it will work out.

Another question, is this type of construction more difficult to extend/renovate? Just thinking that, in future, it might be more worthwhile renovating than trying to move in future - particularly if lenders are wary of the construction type.

Thanks very much,


Topic starter

Hey Marc,

Just back with an update as received our mortgage offer this morning. Bit of a relief after the first lender declined.

We did end up getting a full building survey, although that was purely for our own peace of mind rather than a requirement from the lender. To be honest, I think it helped that we went with the same lender as the current vendors - ended up with a decision pretty quickly.

Thanks for your help.


Admin Admin 11 May 2021 4:18 PM

Fantastic news Tommy!

It's always good to hear when an application goes through despite an initial rejection and illustrates the rewards of perseverance and a little knowledge.

You did it 100% the right way too by instructing a full building survey which is well worth the additional cost, for the security of your investment and peace of mind as you state. 


Congratulations and very well done.


May I wish you the very best in moving forward with your new home, and don't forget if you ever feel like sharing some of the structural details that you notice, or any refurbishment projects you might undertake, you know the place to come to.

Until then, take care, stay safe and enjoy.

Hi Marc