Property Clinic

Windows and condensation and trading down off-season

Q We have a 1950s semi-detached house in Dublin 6W. In July 2012, we spent a considerable amount of money on new windows (F/P white PVC) using a reputable firm. There were a number of problems, including a wrongly-designed window, but most significantly one of the windows broke down (there was water between the two sets of glass), and in some there was condensation which was hopefully dealt with by replacing some defective rubbers between the glass and the frame. To our mind everything was sorted some time after we engaged with the service manager in January this year. Now, however, with the onset of the cold weather we have had condensation on some of our windows in the morning – an occupied bedroom, bathroom and two other upstairs rooms. Please advise on how this condensation can be tackled. One of the reasons we got new windows was to avoid condensation which had appeared on the original iron-framed ones.

A There are clearly two separate issues here; firstly, some problems were experienced during the time of installation of the windows and, secondly, an ongoing problem with condensation arising on the windows.

Let’s look at the first issue. Unfortunately, building is not an exact science and teething problems are not unusual even with reputable companies. The main issue is how the company deals with and addresses the issues as they arise.

I note that the main issue at the time of installation was a build-up of water within some of the double-glazed units. This suggests that the factory-formed seal within the particular double-glazed units failed, and the only effective remedy here was to have the defective units replaced, which we understand has been done. Assuming that these issues have all been addressed, then the initial teething problems will all have been adequately dealt with.


The second and current issue relates to condensation which is now forming on the windows, and I note that this is most evident in the mornings and is apparent on the windows in at least four separate rooms.

Condensation arises as a result of the environmental conditions within the house and the extent of this is dependent on a number of factors including the relative humidity (the amount of moisture vapour in the air), the levels of ventilation, the levels of heating and the insulation standards.

Ventilation can clearly be provided simply by opening windows. However, it is also a building regulation requirement that provision be made for background ventilation to livingrooms and bedrooms and for mechanical extract ventilation to kitchens and bathrooms. Basically, the better the ventilation standards are, then the less the risk there is of condensation occurring.

The levels of heating will also have a significant impact. The warmer the environment is, the more moisture vapour the air can hold and, once again, there is less risk of condensation occurring.

The other issue is the level of insulation to the house. Basically, the better the insulation standard, then the less the risk of condensation occurring.

It is important to note that condensation can be affected by all of these factors, and that simply by addressing one would not cure the problem. Accordingly, it is a myth to suggest that by replacing old single-glazed windows with double-glazed windows you will prevent condensation – however, it will significantly reduce the risk of it.

In order to prevent the condensation occurring, you will need to take the following steps:

Reduce moisture-producing activities within the house such as drying clothes, towels on radiators, clothes horses, etc.

Improve ventilation standards where possible by opening windows more frequently and ensure that mechanical extract fans are serviced and working properly in the kitchen and bathroom. Particular attention should be given to background ventilation within the rooms and you should ensure that your permanent vents are working properly.

Look at your heating patterns and consider extending heating times or at least ensuring minimum background temperatures throughout the colder winter months.

Look at upgrading the thermal insulation standards to the house as necessary.

The first three issues raised involve little or no capital outlay and by taking simple measures, you will notice the improvement almost immediately. The latter issue of upgrading the thermal insulation can be quite expensive and should only be done as a last resort for dealing with the condensation that you are describing.

Val O’Brien is a chartered building surveyor and member of the SCSI,

Q We would like to sell our property and trade down to a smaller house now that our children have left home. We would like to sell now and have been in touch with a local estate agent about listing the property but are nervous we won't find a suitable house because there are very few smaller properties for sale in our area. Is it because this is not the traditional selling season and would you expect there to be more houses for sale later in the year?

A Your predicament is becoming increasingly common and is something of a catch-22 situation. You want to sell your home and trade down but can’t find anything suitable at the moment and so you are nervous about selling your home until you identify a new one. If you find a smaller house that you like and still need to sell your own home, you risk missing out to someone who has access to the finance.

There is a dearth of supply at the moment in some areas and this is largely to do with a lack of mobility in the market. People who might previously have traded up are either in negative equity and can’t afford to move, or are on tracker mortgages and do not wish to lose them by moving. This, combined with very low levels of building and difficulties in accessing mortgage finance, has led to a lack of movement and supply of family-type homes in many urban areas.

The traditional selling season doesn’t really apply anymore and people tend to buy and sell property all year round depending on their circumstances.

I would advise you to do your research and consider all possibilities. I would suggest speaking with your local chartered surveyor and estate agent to see what properties they have coming onto their books in the coming weeks. It may be a case that they are in the process of taking on some new properties in your area. You should do your research on the internet and perhaps consider widening the net in terms of location to give you greater choice.

If you have made up your mind to sell your home, you could consider listing it and perhaps renting a smaller property for a period of time until you find something suitable, but this really depends on your individual circumstances and preferences.

It is not an easy situation to resolve and a decision such as this cannot be taken lightly. Your personal and financial circumstances are key aspects but all you can do is pull all the relevant information together and make an informed decision on the best likely outcome.

Gerard O'Toole is a chartered valuation surveyor and is chair of the western region branch of the Society of Chartered Surveyors Ireland,

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