Sean Wheatley, plastering specialist, answers some common questions about decorative plaster mouldings and the best solutions for repair
QThe moulding is slightly damaged and there are some minor cracks; what is the best method of repairing these?
Minor cracks can be filled using a 50:50 mixture of casting plaster (plaster of Paris) and traditional lime putty.
QA small section of plain cornice is missing – how can a new section be matched in?
Sections up to around 600mm can be formed by hand using a plasterer’s joint rule – a triangulated specialist tool for making good ornate plaster. Larger sections can be run in situ after forming a running mould to match the original profile. This is a zinc template fitted to a wooden base, which is then run through wet plaster to create a cornice and other profiles.
QPart of the ceiling rose is badly damaged. Can replica sections be made?
Missing pieces of a ceiling rose can be replicated either by hand modelling or by taking a mould from the remaining enrichments and casting new pieces.
QHow should new fibrous plaster components be fixed in place?
Fibrous plaster components should be fixed by countersinking stainless-steel screws and using an appropriate adhesive. The screw holes can be filled with fine casting plaster and traditional lime putty.
QWhat should be considered when reinstating decorative plasterwork where none is present? Thought should be given to the period of the property as well as the ceiling height and room proportions. Mouldings were generally more elaborate in areas seen by visitors, with the degree of decoration indicating the status of the house and individual rooms. Try to look inside neighbouring properties that may still have original details.
QIs it possible to take down cornicing and other plaster mouldings during renovation work?
Yes, but it is advisable that this should always be carried out by an experienced plaster conservator.
QIs running in a new moulding in situ feasible or is it preferable to use sections of fibrous plasterwork? Either method is feasible but your conservation officer may insist on a like-for-like repair. Run in situ was most traditional until the mid-1800s, but it is labour intensive. Fibrous plaster is generally quicker and cleaner but not always appropriate to the age of your building.
– decorative lime plastering.
Tel: 01664 561670; heritagelimeplastering.co.uk – architectural plasterwork restoration and repair. Tel: 01959 571135; artisanplastercraft.com – specialist in fibrous plastering, with large historical archive. Tel: 020 8830 1928; butcherplasterworks.com
– specialist plastering, across a range of projects. Tel: 01223 420144; georgecook.co.uk – plaster specialist with in-house sculptors. Tel: 01245 322022; lockerandriley.com – lime and fibrous plasterwork. Tel: 0113 236 0864; ornateinteriors.co.uk
– historic plasterwork.
Tel: 0113 261 4388; plasterrestorations.com – decorative mouldings
Tel: 01525 406690; revivalplaster.co.uk
– plastering specialist. Tel: 01271 883349; seanwheatley.co.uk
– decorative plasterwork. Tel: 01603 400824; stevensons-of-norwich.co.uk