Traditional Lath and Plaster Ceilings


When you are a surveyor ceilings can say so much!

It may seem a strange thing to say but when you have years of experience of surveying properties you get indications of problems and issues from almost anywhere. One common one in older lath and plaster ceilings is to be able to distinguish the different types of cracks that you see. Some properties almost always have cracks in certain areas which are a characteristic of the property. In other properties you can see as a surveyor from the cracking that further investigation is needed.

lath and plaster

Is this a lath and plaster ceiling or not?

lath and plaster

Start at the beginning

The very first thing for a surveyor to do, of course, is to start at the beginning to understand what the cause is. This article looks at how a surveyor would consider a ceiling in a property.

We use lots of sketches and photos in our building surveys

Before we start, can provide help and advice with regard to almost any property problem. We particularly like carrying out building surveys and full structural surveys in older properties, within which we often find lath and plaster ceilings. There can be all sorts of problems associated with lath and plaster ceilings. We are using this article to show you some of the problems that we have come across over the years.

A photo is worth a thousand words particularly in a structural survey

As you can see from this article we use lots of sketches and photos in our reports as the feedback we have from our clients over the years is that the sketches and photos that we use help them understand our reports better and in turn their better understanding ensures that they know the problems or issues that the property has and as such they can negotiate with regards to price on this matter or make allowances and budget for future work. We are more than happy to meet you at the property during the survey to discuss any issues you have and we are more than happy to walk around the property and show you our findings. Please free phone 0800 298 5424 for a friendly chat with one of our surveyors.

What is Lath and Plaster?

Laths are thin strips of timbers which are fixed to the structure. Wet plaster is applied to the laths, usually in several layers. The plaster forms a key as it is forced between the laths. This plaster, once dry, is given further coats and often a paint finish.

lath and plaster

Lath and plaster ceiling

How do we know a property has a Lath and Plaster Ceiling?

There are many ways an experienced Surveyor can identify a Lath and Plaster ceiling. This can be from within the room when they notice undulations in the ceiling or it could be from the age of the property that they know that it is likely to have a Lath and Plaster ceiling. This can then be confirmed while viewing in the roof space and seeing the Laths.

lath and plaster

Lifting insulation within a roof to
check and confirm that it is a
Lath and Plaster Ceiling

lath and plaster

Lath and plaster ceiling exposed due
to plaster deterioration

lath and plaster

Lath and plaster viewed within loft
with boarding removed

Lath and plaster ceilings can take more damp than a modern gypsum plaster ceiling

lath and plaster

Entire ceiling has come down due to
water leak leaving the laths in place

lath and plaster

Ceiling visible in the bath

lath and plaster

If you look closely you can see that
plasterboard has been tacked over
original lath and plaster,in theory
you should be able to re-plaster

lath and plaster

Sketch shows where plasterboard is tacked over lath and plaster which is a technique used to hide defective lath and plaster that is unfortunately relatively common

Keeping our reports plain and simple and using plain English

For example if we use the term Lath and Plaster then we would generally define it for example as below:

Lath and Plaster Defined

Laths are thin strips of timbers which are fixed to the structure. Wet plaster is applied to the laths, usually in several layers. The plaster forms a key as it is forced between the laths. This plaster, once dry, is given further coats and often a decorative finish.

However our definitions and whether we define things very much depends upon the client's property knowledge.

The circles and ovals in our reports

We use the red circles and also ovals in our reports to help to highlight certain things we want to bring to your attention and we also use them to highlight problem areas.

lath and plaster

An example of one of our sketches

lath and plaster

An example of a photo used in a survey.

Other articles that we have written on ceilings and surveying

We have written many articles over the years. We believe that the following may be of interest to you, they are articles written by surveyors on a few related subjects:

New ceilings

The adjacent photo is of a brand new ceiling, some five years old which shows that true craftsmen are still about with the cornice although it does show how easily you could be deceived into thinking that you had an old plaster ceiling.

lath and plaster

New ceiling

Defects in Lath and Plaster Ceilings

Common defects that Surveyors find with this type of ceiling is that the laths and plaster are placed too close together or too far apart therefore the plaster cannot form a key. It can also deteriorate due to dampness within the structure, general vibrations, structural movement and age.

lath and plaster

Lath and plaster ceiling deteriorating
– viewed from the loft space

Some minor hairline cracking to the lath and plaster and possibly areas where the plaster has lost its key or bond to the wall may occur. This is simply due to old age and possibly minor dampness, particularly around the windows and chimney areas.

How builders hide problems in lath and plaster ceilings

Builders may remove lath and plaster ceilings and put a new ceiling up. Also they may put a sheet of plasterboard over the original lath and plaster and tack it into place .

The worst problems we have seen with Lath and Plaster

We must draw your attention to the problems we come across with Georgian properties and Victorian properties when they have what is known as a Butterfly roof.

lath and plaster

Butterfly roof

This is a roof with a central valley and as such can, and often does, leak into the roof and the ceilings. Given the age of the property it is almost without exception that the ceilings are likely to be Lath and Plaster. Therefore we always inspect the roofs, and you do need to know that a Valuation Surveyor may not even look in the roof. We will, if at all possible, and it usually is, get onto the actual roof of a butterfly roof to check the condition, not only of the roof slates but also of the valley gutter as it is so important to ensure that this is watertight as, if the water does get into the Lath and Plaster ceiling it can cause a mess and be very difficult to repair.

Lath and Plaster and Lime plaster

We would also add that Lath and Plaster ceilings were formed in lime plaster. Lime plaster takes a skill to actually use; we would say far beyond the normal gypsum plaster that we typically see being used today in lots of modern properties and unfortunately in older properties. With no disrespect to modern day plasterers, as we certainly can't carry out plastering to the standard that is commonly found, there is a rarity of people that can use lime based plasters and as such any damage to a lime based lath and plaster ceiling can be expensive to repair and you do have to wait some time.

Repairs to Lath and Plaster ceilings

Older ceilings sometimes crack and fail due to a variety of reasons. The best way to repair them providing the plaster has not lost its key with the lath is to use a flat ‘U' shaped cut into the joint area and apply plaster of Paris and then cross line the cracked area with lining paper and decorate the entire ceiling.

Independent Surveyors

If you truly do want an independent expert opinion from a building surveyor we are happy to do valuations, building surveys, structural surveys, structural reports, engineers reports, specific defects reports, home buyers reports or any other property matters. Please contact us on 0800 298 5424 to have a free of charge friendly chat with one of our surveyors.

Our articles

We hope you found the article of use and if you have any experiences that you feel should be added to this article that would benefit others, or you feel that some of the information that we have put is wrong then please do not hesitate to contact us. This article has been written to create debate, we would be more than happy to talk about anything in the article.

The contents of the website are for general information only and are not intended to be relied upon for specific or general decisions. Appropriate independent professional advice should be paid for before making such a decision.

Commercial Property

WIf you are looking for commercial property, whether it is leasehold or freehold, we would recommend an independent survey as this will prevent dilapidations claims in the long run. We use sketches and photos in commercial property reports as often the problems are technically more difficult and in some cases they are at high level as commercial properties tend to be higher and less accessible than a house or home. You may wish to look at our Dilapidations Website at and for Disputes go to our Disputes Help site , both of which we have been advised are very helpful!

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