23 Sep 2019

Renovation of oast houses

Here, Mark Horner of Mark Horner Architects – a specialist in the restoration, extension and conversion of oast houses – reflects on the history of oast houses and raises some important questions before bringing this iconic structure back to life.

Gallery

thumbnail image

Oast houses are special buildings used traditionally for the drying of fresh hops. They were either purpose built or adapted from older farm buildings. These iconic structures are located on the clay soils of Kent and Sussex, where hop gardens flourished in previous centuries and provided hops for the local brewing industry. Oast houses bring their own distinctive charm to the landscape, with their circular drying kilns or ‘roundels’ surmounted by conical roofs and distinctive cowls, and are highly sought after as character homes.

The roundels were constructed with a slotted drying floor with a fire underneath to dry the hops. The roofs are steeply pitched to channel the air upwards to the cowls, which are made of timber and turn to face out of the prevailing wind, allowing the rising warm air out and preventing the rain from getting in.

The remainder of the building comprises a rectangular stowage with a storage floor at ground level, and a cooling floor at first floor. The cooling floor is set down three of four steps below the drying floor; after the hops had been dried they were transferred to the cooling floor, then packed into bags by the packing machine that lowered them down to the ground for transportation to the local brewery.

The renovation of an oast house is often challenging, as they were built by farmers for agricultural use, not for human habitation. Most of the 5000 or so known oast houses have either been converted into dwellings or demolished. Those that remain are usually tightly controlled by the Listed Building Officers of the local councils.

As with any renovation project involving a historic building, there are myriad things to consider:

Is the structure sound or does it require major works to provide structural stability? Most oast houses don’t have foundations and would therefore require underpinning, moreover, the clay soils mean that the building is likely to have moved in its lifetime, particularly if there have been trees nearby.

Is the external envelope water tight? Does it require extensive repair works to the historic fabric – the windows, walls, roofs and such? How can it all be insulated while still allowing the building to breathe? Can the internal finishes be upgraded to modern standards, while retaining the original character? After all, when refurbished they must be able to meet the needs of the families living in them.

Does the layout of building lend itself to use as a house without losing any of its historic features? Is there enough headroom to the stairs? Are there windows to habitable rooms? Can new walls be introduced to form appropriately-sized rooms?

Oast houses are generally narrow so it is best to avoid corridors that cut into the width and opt for an open-plan arrangement instead. There may be historic openings which could perhaps be negotiated as new windows; alternatively, it might be possible to glaze the oculus and let light in at the top under the cowl.

And finally, does the setting of the building present any challenges? Oast houses were generally built in close proximity to working farms.

Although initially daunting, with the input and guidance of a good architect, a really good conversion is certainly a worthwhile investment, creating a valuable property with a unique sense of character and style.

Further information....

Rate this item
(0 votes)
Login to post comments