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Sunday, July 27, 2014

Who is managing build quality these days? – Part 1

Guest article from Joe Malone BSc(Hons) ICIOB

'I have worked on a high number of complex building defect investigations over the last 6 months and most of my conclusions have proven that poor build quality and hidden latent defects are to blame'

My work as a consultant building pathologist has led to me forming a strong view that build quality simply isn’t adequately managed anymore. I have worked on a high number of complex building defect investigations over the last 6 months and most of my conclusions have proven that poor build quality and hidden latent defects are to blame. Some might blame the demise of the traditional clerk of works role to oversee build quality but I have formed a view that clients are simply becoming too trusting. It costs money to run with a client side surveyor and why bother when you’re working in ‘partnership’ or ‘collaboratively’ with your contractor? They allow contractors to self manage build quality or they trust to building control inspections and take further comfort in the fact that they purchased an NHBC guarantee.  You may well be shocked at some of the things I encounter during my survey work so I thought I would give you a flavor by way of sample of some case studies on recent survey reports I carried out in London.

Case Study 1. Overflowing with Defects

Fig 1. Balconies not draining - Source: Authors Own
You will notice the decorative spoiling to the underside of the balconies in figure 1. The square steel stanchion you see is also the rainwater downpipe that the balconies drain into. There is only one outlet for each balcony and the balcony is covered with timber decking that sits above the asphalt coating on a Harmer Uni-ring raised floor support system, as seen in figure 2 below.  This was included in the build specification that I managed to get hold of. It was rather a shame that the clients quality control manager (if they had one) didn’t also get hold of it because then the client might have seen that the system was completely omitted and replaced with larger timber battens directly screw fixed through the bituthene membrane on the balconies.

This Harmer system was meant to provide a dual role:

1.  To raise the timber firrings off the balcony tray to allow rainwater crossflow to the single balcony outlet.

2. To provide a fixing system for the timber firrings, thereby preventing the bituthene membrane from being punctured.

Fig 2. Harmer Uni-ring system that was meant to be installed on balconies - Source: http://www.alumascroofing.co.uk
Screw fixing timbers directly through the bituthene membrane on the balconies was not a sensible thing to do but the second issue was that solid lengths of timber battens fixed to the floor meant that there was no crossflow of water to allow it to reach the single drain point. The net result was that rainwater spills over the edge of the balconies and tracks back underneath balcony ceilings causing the decorative spoiling that can be seen in figure one. This development is circa 10 years old and the problem  has existed and remained undiagnosed from day one.  I am still staggered that the developer managed to get away with this. 

Case Study 2: The Lost Art of Parapet Walls

This case proved two things, one, that the high cost of property does not guarantee a better build quality and two, that no one seems to know how to build a correctly detailed parapet wall anymore.

I was appointed to investigate the cause of water ingress into a very expensive residential block overlooking the Millennium Dome. Water ingress was affecting one flat in particular below the top floor penthouse. As such most of investigation work was focused on the top floor (See figure 3 below).

A perimeter parapet wall surrounded the balcony and there were a couple of visual tell tales that made me suspect that all was not well with the parapet.

1.  No visual sign of a dpc under the copings.
2.  Cracked mortar joints between copings
3.  No sign of weeps on either side of the parapet wall
4. Parapet stone drips were compromised on the outer ledge by the installation of fibreglass decorative cornice that was too wide for the application and therefore covered the coping stone drips causing significant water staining on the outer face of the parapet wall.

It was obvious to me that a coping would need removing to fully inspect the parapet and you can see in figure 4 below what I uncovered. This is as bad as it gets for parapet wall detailing. The dpc was too narrow for application, it was sagging into the cavity due to the lack of a hard support to bridge the cavity and there was no effective cavity tray or drip details installed in the parapet. I even found a couple of old joist hangers thrown into the cavity. 

Fig 3. A good view from the penthouse balcony   - Source - Authors Own 
Fig 4. A bad view from the penthouse balcony - Source - Authors Own
You may be able to see in figure 4 how the timber batten on the outer ledge compromises the drip detail on the underside of the parapet coping stone. The fibreglass decorative cornice was fixed to this.

I’ll let you hypothesize what a very nice penthouse flat with this sort of view might cost but it had no relationship to build quality, which was quite shocking. 

In next week's article I will provide some further examples of poor building practice which could have been avoided if the build quality was managed more effectively.

Joe Malone BSc(Hons)ICIOB
Malone Associates Ltd

Please feel free to share this article and other articles on this site with friends, family and colleagues who you think would be interested

Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.

Sunday, July 20, 2014

Victorian Houses - Part 3 – Some typical defects

Interestingly, condensation is likely to have been less of a problem in Victorian times than it is today! 

Source:  http://www.victorianweb.org/
In my previous two articles; Victorian Houses – Part 1 - Dwellings of character but not without their problems! and  Victorian Houses - Part 2 - Typical characteristics  I have discussed some of the characteristics of Victorian houses and also considered some of the difficulties that would have been encountered for those who have lived in these houses at the time.  While it is true that Victorian houses can be both interesting and quirky, they were not designed or built to anywhere near the standards we see in modern houses today and as such are prone to a number of building defects. In this article I will discuss a selection of typical defects that may be found in Victorian houses.

Source: http://www.heritage-house.org/
Firstly and arguably one of the biggest differences between Victorian and modern houses is the approach to (or lack of) thermal insulation.  Victorian houses would invariably be constructed using solid brickwork walls, usually 225mm (approximately 9in.). There would be no insulation or damp proof membranes (DPM) in solid ground floors and no insulation in roof spaces.  Air tightness was not a consideration and heating was usually limited to an open fire in the main room of the house.  Basically these buildings were cold at certain times of the year and as such were susceptible to damp. 

Source: http://www.1stassociated.co.uk/
Damp in a building can occur in a number of ways and will be influenced by construction details as well the internal and external environments.  You will find information on rising damp and condensation from following the links to previous blog articles so I therefore do not intend to discuss the ‘science’ of damp within this article, It is worth however appreciating that Victorian buildings are particularly vulnerable to damp unless of course remedial works/upgrading/refurbishment or whatever you want to call it are carried out. Interestingly, condensation is likely to have been less of a problem in Victorian times than it is today!  Nowadays we emit huge volumes of water vapour into the air tight environments of our modern dwellings due to things such as showers, drying cloths on radiators, use of tumble dryers and portable gas heaters for example.  None of these things existed in Victorian times and in addition to the fact that Victorian houses were not air tight and in fact they were quite draughty this conversely provided a good level of natural ventilation that would provide regular air changes which would reduce the risk of condensation. 

Source: http://www.scotlandschurchestrust.org.uk/
Nail sickness is something that can be found on Victorian House on roofs.  Nowadays, galvanised or non-ferrous fixings are used to secure roof tiles to timber roof laths however In Victorian times nails would have been ferrous (contain Iron), without any other coating or protection and as such would have been vulnerable to corrosion.  The vast majority of original roofs would have been replaced, sometimes a number of times, so this is less of a problem nowadays.  A good indicator of whether nail sickness is occurring will be loose or displaced roof tiles. Roof tiles can become displaced for other reasons so it is important to take into account the age and type of the building before deciding.

Source: http://bentleyheritage.com/
Cast iron was widely used as a material for rainwater gutters and downpipes in Victorian times however it is less commonly found nowadays as many gutters and downpipes have been replaced with UPVC.  Over time cast iron can be prone to corrosion if not maintain regularly which often results in other defects associated with rainwater leaking and saturating the building fabric which can lead to penetrating damp.  With the rate at which steel and other metals has increased over the last few years, cast iron has become very expensive.  Therefore, replica materials are sometimes used when restoring Victorian properties to provide original character features at an affordable cost.

Source: http://www.spabfim.org.uk/
Houses constructed in the earlier Victorian period were constructed using red brick which were softer and less durable than later bricks and lime mortar. The use of cement in re-pointing mixes is generally considered as detrimental when replacing mortar that would have originally been lime based, resulting in accelerated decay and damp problems. A characteristic of mortars containing cement is their vulnerability to salt and possible sulphate attack. Also, the porosity of softer bricks is greater than the latter more durable bricks and as such have the ability to retain large quantities of water/moisture.  If bricks are not allowed to dry out, then any trapped moisture within the bricks will freeze during sub-zero temperatures.  When water freezes it increases in volume and will therefore expand within the pores of the brick often resulting in the face or the brick becoming detached and falling away (this is referred to as spalling).

Victorian houses are prone to a whole range of defects that are also common with other types of buildings. The examples I have provided above are far from exhaustive however provide some information on some typical problems that may be found in Victorian Houses.  For more information of building defects please refer to the links within this article and also take a look at my blog archive at the right hand side of this article, where you will find a range of different articles on building defects, historic buildings and much more.

Please feel free to share this article and other articles on this site with friends, family and colleagues who you think would be interested


Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.

Sunday, July 13, 2014

Victorian Houses - Part 2 - Typical characteristics

Victorian houses are very distinctive and can be identified by a number of typical features and characteristics

In last week’s article 'Victorian Houses – Part 1 - Dwellings of character but not without their problems!' I discussed how Victorian houses seem to maintain a great deal of character and history compared to the vast majority of houses that we build today.  Despite this I also considered the difficulties that would have been encountered by those living in Victorian houses prior to the introduction of some of the more modern facilities that we take for granted today, such as insulated walls, central heating, internal WC and bathrooms etc.


This week I would like to focus on some of the typical characteristics that make Victorian Houses different from most other types of houses. In Part 3 next week I will consider some of the typical defects that may be found in Victorian dwellings.  If you are considering buying or renting a Victorian house you may find this information of interest.


Bay Windows incorporating sheet glass
Source: Own
Iron Railings - Many Victorian Iron railings were removed during the Second World War to make ammunition, however those that were not removed or perhaps have been restored may look like the photograph below.


Source: http://idostuff.co.uk/blogs/2010/reclamation-cast-iron-railing-fence/
Flemish Bond Brickwork - This bond is formed when bricks are laid alternately at their longest side (stretcher) followed by their shortest side (header) with the sequence repeated.  As you can see in the image below the next course is laid in the same way with the headers located at the centre of stretchers below.


Source: http://www.pavingexpert.com/
Patterns in the brickwork made from coloured bricks - This is not a feature of every Victorian House however due to the rapidly expanding availability of bricks and developing transport networks, the Victorians started to experiment with bricks to provide decorative features to their houses


Source: http://thedomesticsoundscape.com/
Stained glass in doorways and windows - This is something that became a common feature in Victorian houses and evolved into the Edwardian period which followed


Source: http://www.corianderstainedglass.co.uk/
Slate Roof Coverings


Source: http://www.k-roofing.co.uk/
Narrow Roads and No Garages - Cars were not a consideration in Victorian times so there would have not been a requirement to accommodate traffic on roads or to provide garages.  This is why we will often find travelling along Victorian streets nowadays is sometimes problematic, due to parked cars on both sides of the road


Source: http://billdargue.jimdo.com/
Sliding Sash Windows - Sliding sash windows are those that open vertically, usually be means of sash cords and weights. Most windows nowadays are casement types (hinged), although sash windows are still used today particularly in restoration works. 


Source: Image courtesy of Graham Stead
Outhouse Toilet - This is something that was discussed in last week’s article and in particular how uncomfortable it would have been using the toilet in cold weather and in the middle of the night!

Source: http://www.gower-images.com/
Tiled Entrance Halls 

Source: http://www.mintontiledfloorcleaning.co.uk/
Cast Iron Fireplaces - Unlike modern houses which may have a ‘feature’ fireplace in one or two rooms, Victorian houses incorporated cast iron fireplaces such as indicated below, in most of the rooms within the house including all of the bedrooms.


Source: http://acdbuild.co.uk/
Next week in the final part of this ‘mini series’ on Victorian houses, I will consider some of the typical defects that may be found.  Be sure to take a look!

Please feel free to share this article and other articles on this site with friends, family and colleagues who you think would be interested

Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.

Monday, July 7, 2014

Victorian Houses – Part 1 - Dwellings of character but not without their problems!

Living conditions in the vast majority of Victorian houses would not have been easy and justifies the need to improve living conditions through regulation


Source: http://www.felixstowepropertynews.com/
Approximately 18 months ago I wrote an article which compared the difference and characteristics of living in a modern dwelling compared to an ‘older’ one. Within the article (Link) I also discussed the impact of ever changing regulations and how this is having and influence on house design and construction:

It has been a requirement for many years under UK Building Regulations to construct buildings with high level of thermal efficiency and this is something that is constantly being amended to make buildings even more thermally efficient and air tight than ever before.  So, the decision to live in a more ‘modern’ building will often revolve around this higher level of thermal comfort and modern facilities that these buildings offer.  Many seem to be prepared to accept these, sometimes characterless, standardised houses, with perfect right angles and flush plastered walls, which seems to be the conventional ‘norm’ for those buying modern houses today.  Accepted, there will always be some exceptions where those constructing new houses will try to incorporate architectural and period features however these are few and far between.  The reason this is so rare is usually because of a desire to squeeze as many plots onto a site as possible, to be built as cheaply as possible and to therefore maximise return.  There is also a general reduction in available traditional craft skills, which are being lost as older craft workers retire and colleges fail to teach new ‘apprentices’ these craft skills.

Victorian Minton Floor - Source: http://www.mintontiledfloorcleaning.co.uk/
Modern dwellings have many positive attributes however in general terms there is a lack of character compared to certain types of older houses.  Take the Victorian era for example, where in most cases you get a real sense of history from the moment you approach the dwelling and especially when you walk through the front door.  This of course is on the assumption that the dwelling has not been modernised or refurbished to a point where most or all of the character features have been removed! It is true that you could argue that you cannot get a sense of history from a modern dwelling because this can only happen over time, however,  in all honesty it is difficult to see how future generations will look back at our current stock of modern houses in the nostalgic way we can now look back at Victorian houses.  Despite this, living conditions in these dwellings in Victorian times would not have been easy as we will see below, and justifies the need to improve living conditions through regulation.

Victorian back to back house - Source: http://www.weekendnotes.co.uk/
It was during the Victorian period (1837 – 1901) that the development of the railway network in the UK really evolved which for the first time allowed transport of large quantities of materials throughout the UK.  Prior to this house builders primarily made use of local materials.  At about the same time bricks were starting to be mass produced which resulted in them becoming more affordable and used much more widely throughout the UK. Although this allowed dwellings to be constructed more widely many of the working class Victorian population, particularly in towns lived in poor quality accommodation often with large families sharing just two rooms, one downstairs and one upstairs.  These types of houses became know as ‘back to back’ houses, because three of the four walls were shared walls with other dwellings.  For a moment just image this environment with only one main entrance door to the front and one window on the ground and first floor of the front wall only, resulting in poor natural lighting, limited ventilation in addition to poor sanitation. These would not have been comfortable houses to live in!


Source: : history.powys.org.uk/
Not all Victorian people lived in back to back houses and terraced and even semi detached house were constructed in large numbers, which are largely the types of Victorian Houses that you will see throughout the UK today. Hygiene and sanitation in Victorian houses was a particular problem.  Bathrooms, as we know them today did not exist in the vast majority of Victorian Houses.  Most families would own a steel bath, which would be stored in a small yard (if they had one) and brought in once a week and placed it in front of the fire, which was the warmest place in the house.  The whole family would use the bath with the water topped up to keep it warm.  Also, there would have been no running water to the vast majority of Victorian houses.  Each house would collect their water from a water pump (see image above), which would be located somewhere in the street outside.  Anyone who was unlucky enough to live at the wrong end of the street would have quite a journey carrying buckets or containers of heavy water to supply their dwellings.


Source: http://rememberwhen.gazettelive.co.uk/
Using a toilet in Victorian times would also have been an experience.  Most toilets were located in an outhouse at the rear of the property.  Many of these are still present today, however thankfully in the vast majority of cases, WC facilities have been moved into the main dwelling, usually within the bathroom.  These former WC outhouses started to be used as coal sheds, however with the rapid decline of coal use they were used for general storage.  Again imagine yourself needing the toilet in the middle of the night in the depth of winter.  You would need to get out of your nice warm bed into a cold house (solid walls with no insulation and no central heating I’m afraid!), find your way to the outhouse in a poorly lit building, go outside into what could be sub-zero temperatures and even snow and then use the toilet!  This does not sound like a lot of fun does it, and should help us to appreciate the facilities we have available today.

Despite the character, charm and sense of history that we can get if we live in or visit a Victorian house today, it is fair to say that the vast majority of those who lived in these houses in Victorian times would not have felt the same.  In part 2 next week I will identify some general characteristics of Victorian houses and in part 3 the following week I will discuss some typical defects. Be sure to take a look at these articles.


Please feel free to share this article and other articles on this site with friends, family and colleagues who you think would be interested

Information/opinions posted on this site are the personal views of the author and should not be relied upon by any person or any third party without first seeking further professional advice. Also, please scroll down and read the copyright notice at the end of the blog.