Joinery
Many historic buildings retain a great deal of original interior joinery, such as doors, windows, shutters, staircases and panelling, as well as skirting boards, dado rails and picture rails. Joinery detail is a major element of the character of a historic building; inappropriate replacements can ruin the proportions and historic 'feel' of the original design.
Modern doors and windows in uPVC, aluminium or tropical hardwoods are particularly unsuitable for historic buildings, the first two because they hinder the building's ability to breathe, and the latter because their use is unsustainable and, in general, historically incorrect. While some of the grander houses had mahogany doors, and a great deal of oak was used in churches, almost all 18th and 19th century joinery was constructed of softwood and then painted; such joinery was never left in a stripped condition. Unacceptable uPVC and aluminium window details include stuck-on glazing bars and imitation sash windows (often with Georgian or Victorian pane patterns), which open outwards.
Regular maintenance is the key to smoothly operating timber sash windows and there are successful draught proofing systems available. Joiners, specialising in window repair, can routinely repair timber sash windows, and scarf in missing or damaged portions of timber windows, shutters, panels etc.; this should be carried out on site, where possible. It is preferable, when choosing a joiner (and particularly so when the quantities required are not significant), to select one who is capable of making up his/her own tools and is used to making handmade bespoke joinery. The more commercial joinery suppliers use high speed equipment and, for conservation work, may have to have special cutters made up by specialist manufacturers, which can be expensive and take time.
External appearances can deceive and many a timber window, shutter and panelling, capable of being repaired, has ended on a skip, because it looked beyond repair (usually from overpainting or lack of paint). An experienced eye is needed to assess the true condition.
When dealing with the steel windows of the earlier part of the 20th century, any appearance of rust should be dealt with immediately, by shotblasting to SA21/2 and priming immediately.
Note 1: all joiners were asked to indicate if they had experience in repairing sash windows, and in accurately replacing sections of moulded timber on windows, doors, panelling etc. Those with an asterisk beside their name replied in the affirmative to both questions. Where a joiner has experience in only one of these skills, this is noted in the entry information.
WOODCARVING As well as in the repair of antique furniture, the restoration of timber architectural detail such as intricately carved corbels, complicated shopfront details and chimney pieces will require the skills of the expert woodcarver.
TIMBER DECAY All historic timber is vulnerable to rot and decay. Wet rot and dry rot are wood rotting fungi, which are a form of plant. Without water, plants die so not surprisingly, the ingress of water and moisture into a building is the prime source of such problems. Regular maintenance checks will prevent this happening but, if rot occurs, it is essential to locate and eliminate sources of damp, before treatment is carried out.
Timbers should be isolated from damp masonry in areas of risk and with minimum cut back. Traditionally, where joists were infected with dry rot, it has been the practice to cut back the joists to at least three feet from the outbreak; also toxic chemicals were used. Nowadays, less invasive and dramatic ways are being used to treat dry rot. Experts experienced in dealing with such problems and with up-to-date knowledge, should be consulted prior to any work being carried out.
Embedded wall timbers in 18th and 19th century construction can become decayed and, when this happens, can give rise to alarming structural behaviour in walls, such as outward movement of masonry, and detachment of the outer skin from the inner leaf. However, once the problem is ascertained, it is often possible for an experienced conservation professional to stabilise the structure by means of relatively small repair procedures.
Further Reading
Conservation Guidelines
No. 3 Windows, No. 5 Interior Joinery/Fittings, No. 11 Rising Damp/Timber Decay Department of the Environment/Irish Georgian Society 1996
Keohane Frank, Editor,
Period Houses, A Conservation Guidance Manual - Dublin Civic Trust Dublin 2000
Cruickshank, Dan and Wyld, Peter
London : The Art of Georgian Building (Architectural Press). Oxford, 1975
Nicholson, Peter The New Practical Builder London, 1825
Ashurst, John and Nicola
Practical Building Conservation:
Vol. 5 Wood, Glass and Resins (English Heritage). Aldershot, 1988.
Ridout, Dr. B.V.
The Control of Dry Rot. Church News, 1986.
Ridout, Dr. B.V.
The Gently Way with Dry Rot (SPAB News).
Thomas, Andrew
The Treatment of Damp in Old Buildings
(SPAB Technical Pamphlet no. 8). London, 1986.