Rats and Mice

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Rats and Mice

There’s an urban myth that you are never more than 6ft (2 metres) away from a rat, but where does this come from?

According to the BBC News Magazine, it may derive from the former Ministry of Agriculture. They circulated many public health announcements to promote hygiene in homes.

An expert has recently estimated that there are around 10.5 million rats in the UK.“The maths for working out the average distance to a rat is a bit rough and ready because rodents are not evenly spread.It makes sense to discount all the rats on farms, because the phrase is most often used about cities. That leaves us with about 3.1 million urban rats.

Urban areas in the UK cover around 16,000 square kilometres. If we distribute the rats evenly across the urban areas, which is clearly unlikely but necessary for the calculation, each rat has a rather spacious 5,000 square metres to roam around in.

Assuming you’re standing at a given spot in an urban area you would be at most 164ft (50m) away.Saying you’re always 164ft away from a rat doesn’t have quite as much of a fear factor as 6ft away, but it’s a much more realistic estimate.”

However, this statistic would not help the Marketing Departments of pest control companies!

Which properties are most at risk?

Is the house near countryside, a naturalised graveyard, a watercourse  or commercial warehousing?Then rodents  (especially rats) are likely to be around in the vicinity.

There is also a known link between the increased fashion for keeping  chickens in urban gardens and rat numbers in the locality. This is most likely due to the freely available food. Chicken numbers appear on the increase as do rat numbers. So when undertaking inspections, we often have a look in neighbouring gardens for chickens. Bird feeders are also a good way of providing fast food for rats, who can climb poles with ease.

We carried out a job in  Long Ashton where the rats were bold enough to sit and watch us carrying out the drain survey-  as can be seen on our blog picture.

How can you tell ?

Anecdotally , we would suggest that 50% of the properties we visit in Bristol show evidence of either historic or live infestation by rats or mice.Rodents  tend to prefer properties that are uninhabited where they can live undisturbed.  Hence a vacant property has a greater likelihood of being actively infested.

During the course of our inspections in the less entered parts of properties such as loft spaces, drains and sub floors, we often come across evidence of rodents. This can be faecal matter, dead rodents, chewed building materials or grease marks on regular runs where rodents have been travelling.

The easy way to tell difference between rats and mice infestations is the size of the faeces. Mouse poo is very small at around 3-5mm in length and very thin, say 2-3mm. A rat poo is longer at around 10mm to 20mm in length and a lot fatter at around 5-8mm.

The drains often provide evidence of faecal matter.  This can give an idea as the extent and length of time the infestation has been live, but at least they are not in the main house. The soil pipes entering a house may offer a good route for rats to enter a loft void.

Again, it’s stated that if you can put a biro through a gap, then a rat can enter. This is a very small gap and one that is frequently found, especially in older housing.

So the presence of rodents is very common although worrying to our clients. The idea of vermin inside their house is extremely concerning for urban householders! However we have become accustomed to finding it in Bristol and we note it at the end of our reports.

What can you do about it?

Rat traps are available in hardware stores and garden centres, as well as on-line. They are much stronger than mouse traps and need setting with care. Chocolate spread and peanut butter are often recommended as bait. You can also buy a variety of poisons from branded suppliers. Mice are easier to trap – being inquisitive, they will try anything (once!).

Sonic deterrents are also available, although mixed results are reported.

If it’s a big infestation, most people assume that the local Council will arrange and pay for pest control. However, nowadays there is generally a charge for this service, even for an advisory visit. The advice may well consist of ‘Buy some poison from Wilko’ !!

Large numbers of private pest control companies operate in the sector. Some are regulated by the BPCA (British Pest Control Association) which gives an added layer of security for the customer.

But unless their sources of food and comfortable lodging are removed, the rodents are likely to return next autumn…

 

 

Airbricks through the Ages

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Airbricks through the Ages

Older properties with suspended timber floors are prone to dampness in the space beneath, in the sub floor void. This may be caused by condensation or by rising damp or by penetrating damp. It is likely to cause rot, decay and timber beetle infestation (woodworm  or worse).

Airbricks are essential to permitting air to flow beneath the floors. This reduces the condensationin the sub floor void. It removes excess moisture and helps the timbers to remain drier – hopefully dry enough to prevent that rot, decay and timber beetle infestation.  These seemingly insignificant objects are often overlooked but their role  isvital in keeping the ground floor timbers floors in acceptable condition.

What may be the consequences?

Sadly,landscaping gardens is one of the major causes of blocking airbricks. For example, the grilles may be covered by wall plates for decking or in some cases simply heaped with gravel. Building pathology is not a widely appreciated topic in all trades! Recently, we visited a property in Bedminster on behalf of an insurer where decking had been installed to the rear and caused a significant dry rot outbreak.  Unfortunately for the policy holder, this would not be an insurable peril and she will have to fund the cost of treatment and repair as well as replacing most of her stripped wooden floor.

Victorian Airbricks

The Victorians used a cast iron grille with vertical vents, as shown on the below diagram.  These have rarely been cleaned and over the years become blocked by spiders and general detritus. Often they have been painted so many times that the width of the grilles is reduced. This in turn will impair their ability to allow air to pass under the building. Hence it is important to scrape off the excess paint (wearing  gloves as the paint was often lead containing) and repaint  them.  Pipe-cleaners are useful to help clear the slots.

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In the 1930’s

At this time, the metal grilles were often  constructed in a grid pattern as shown below. Again, they suffer from the same issues as mentioned above; they require clearing out and generally maintaining. If they rust they will expand, which can cause localised cracking to the surrounding brickwork – the force is sufficient to push this out of alignment.

On a building survey in St George recently, we inspected a house that appeared to be completely Victorian, however the airbricks were clearly 1930’s and were not replacements.  We followed the trail and discovered that the house was rebuilt the late 1940’s,having been destroyed by bombing in the war. The smallest clues can help identify issues such as this!

 

From the 1970’s

During the 1950’s and 1960’s, solid floors (of poured concrete) were common hence negating the need for airbrick ventilation. After this, suspended timber floors once again became popular. The accompanying airbricks consisted of plastic louvre-type vents with a slight slope to the fins.  This helped reduce penetrating dampness problems and restricted the opportunity for rodents to enter the sub floors. Again, these vents do require clearing out.

 

From the 1990’s

Even if the floors are of the block and beam construction common in the 1990’s and noughties, air vents are fitted to help ventilate the space. They can also form part of radon control measures so again should not be blocked or removed.

Sometimes larger square vents are seen on the front elevations of houses whichare above the internal floor level.  These are usually installed to help increase air flow for internal combustion appliances such as back boilers or gas fires – they should not be confused with airbricks that are normally brick sized, used to ventilate sub floors.

The future of Airbricks

The insertion of a solar powered fan would greatly assist in ventilating buildings. This would be beneficial in reducing  the many problems associated with damp sub-floors over the last 150 years or so. Such fans are available in other countries but are not found in the UK. They are inexpensiveto produce and would offer significant savings on reactive maintenance as well as preventing decay in sub floors.

 

 

The Beast from the East is Snow Joke

The Beast from the East is Snow Joke

When we are explaining the findings of our Building Surveys, our clients often ask why sarking felt is so important. It’s only a softish layer fastened under the tiles or slates ! Why is its detailing (finish) so vital to the weather tightness of the building? It is intended to act as a defence against snow and wind-driven rain getting beneath the tiles and into the attic.  The snowfalls of winter 2017-8 have dramatically highlighted the importanceof this!

Over the past few weeks our insurance team have been visiting dozens of houses affected by the “Beast from the East”.

The first thing most policyholders notice is water dripping through the upstairs ceiling.  Then when they check inside their roof, they find soaking wet insulation. So why hasn’t the roof leaked before? The direction in which the wind is travelling and its ferocity finds even minor gaps in the sarking felt. Many roofs survived the prolonged snows of 2012, the “Deep Freeze” as it was called then. Why? Because these did not come with the same wind levels and associated snow drifts.

What about Insurance cover?

These ‘small rips’ in the sarking felt can result in a great deal of damage, especially to the ceilings directly beneath. And insurers are unlikely to cover re-felting or associated roofing work because the rips were pre-existing.

However, some owners have extra ‘accidental damage’ insurance cover to the building. Then damaged loft insulation and ceilings resulting from the snow melting into the habitable spaces beneath may be covered.

Who is at risk?

The occupants of one 1930’s house said they had had a survey whenthey bought the property a few months previously. It was a “homebuyer’s report” and the roof was flagged as amber. This indicated that the roofwas acceptable from a surveying perspective. Had we carried out our full building survey, we would have suggested replacing the roof – it had original clay tiles and poorly lapped felt. The felt was probably fitted in the 1970’s when it was common not to overlap the felt sufficiently.The consequence of the poorly overlapped felt was a very wet ceiling.

We also visited a property constructed in the 1970’s with the original roof still in place.There was a gap of some 20mm between the sheets of felt; again snow leaked into the roof void as a result.

It is not just older buildings that have seen snow ingress into roof spaces. We have visited some that are only 5 years old. Here, the clever ventilation details around the ridges and eaves have allowed the wind-driven snow to enter the loft spaces. This has caused considerable damage. Since recent insulation is much thicker( some 270 mm),  it took some time for the problem to become apparent. The result was either larger stains or in one case the insulation was so wet the weight of water caused the ceiling to fall in. These types of ventilation detail are great in helping the properties to breathe. However, water ingress had not been revealed as an issue until tested by the recent snow and strong winds.

Re-building costs

What about Re-building costs?

Sometimes people ask whether re-building costs form part of our survey. Some surveying companies will do this for you and will charge a couple of hundred pounds for the privilege. We don’t because it isn’t really necessary; it adds little value and the professional indemnity insurance cover required would increase our survey fees.

“Sums Unlimited”

So what are your options?  The comparison websites such as MoneySupermarket.com  and GoCompare have made insurers attempt to compete by giving quick quotes and on a level playing field.  Hence most of these quote are based on “sums unlimited” for the value of the property. In reality “sums unlimited” is normally limited to £1,000,000. Many insurers do not insure properties with more than five bedrooms for this reason.

Calculating Re-Building Cost

However, if you are using an insurance broker they may ask for the re-building cost. If this is something you require, it is very simple to calculate! You need to measure the building’s footprint that is, the gross external area of the property. If this is something you want us to do as part of the survey inspection,  please let us know and we will take the external measurements for you.

Count the number of bathrooms (not including any cloakrooms) and add the number of garaged parking spaces. Create a log in on https://calculator.bcis.co.uk/calculator/calculator.aspx and input this data. This will produce a cost for a property band rather than an exact value. Hence you have to make a judgement as to the quality of fixtures and fittings;  we suggest erring on the side of caution with a higher figure for these.

Index Linking and Under-Insuring

Your insurance should have these values index-linked as inflation and other costs will increase the rebuild cost over the years. Hence it is good practice to revisit this valuation every few years. If you make changes to the property such as an extension or add garages, then the rebuild cost will no longer be accurate and will need to be re-calculated. The increasing trend for “sums unlimited” cover stops this hassle unless you have a mansion or a Central London property. It also avoids quibbling should a claim arise.

It is very important not to be under-insured. Sadly, you normally only find this out when you come to make a claim and the loss adjuster checks the figures. If for example you have an out-of-date rebuild cost of say £100,000 and the adjuster says the rebuild cost is £200,000 then you are 50% underinsured.  As a consequence, you will get only half the suggested pay out of your claim.  In the event of a large loss, for example through sudden flooding,  this can be a significant sum of money!

 

 

Reviews and Domestic Surveys

Reviews

We can tell you about what we do – but only our Clients can tell you how well we do it !

Our surveying practice has been operating round the Bristol area for over ten years so we do have a substantial track record.  We have been appearing in reviews by our clients on various websites since 2011. A building survey is an ‘occasional purchase’ and it is essential to choose someone who is trusted. All our reviews are genuine. We do appreciate that buying a house is a stressful time ! But we gently ask our clients to post a review if they are pleased with our services.

Where can you find us?

Click on the heading to read our our reviews

FreeIndex

We set up our profile on FreeIndex in 2011. Here we are ranked 1st out of the  802 surveyors listed on it nationwide. We have  130 x 5* reviews and one 4* review.  The FreeIndex algorithm verifies that the reviews come from individual email addresses with separate ISPN numbers.It flags up and rejects any suspicious reviews.

Google

Google was a harder review site to set up as the business needs to be found on GoogleMaps. We are a  ‘virtual business’ to minimise overhead costs for our clients! Hence we did not start asking for Google reviews until two years ago. We’ve already gained 18 x 5* reviews on the Google platform.

Yell

For a while,we used Yell and picked up 12 great reviews.  However as we no longer pay to advertise with them, our entry rarely pops up in searches.

Facebook

Recently we have started asking for Facebook reviews and have seen some clients come direct from there. The reach of social media is growing. So it makes sense for us to share with you who we have worked for and how they rated us!

Three Best Rated

We came across this site called three best rated. Another independent site, they select the top three businesses in a locality, using 50 different indicators. They clearly do their homework as they rated us in their top three Surveyors in Bristol.

Our promise

We refuse to “make up” reviews . We agreed that we are always wary of those “testimonial pages” where the reviews could have been written by the business. You never see a 4* amongst such collections published directly on a website.

Faked reviews have been a hot topic in the media as these give a false impression as to the quality of the service provided. Recently we looked at some of our competitors’ reviews on various sites.  One had amassed 35 reviews in a single week which we felt was unlikely to say the least; the site in question does not verify such posts.Take a look at the timeline of the reviews that have been left on a site and make up your own mind!

And if we work for you and you are not pleased with our services, tell us so we can remedy any issues. And you think we exceeded your expectations, we would be delighted if you were able to find a few moments in your hectic day to leave a review for us,too !

 

Non Traditional Construction (Part 1)

The Laing Easiform

The Laing Easiform

 

These were constructed by John Laing builders with the first house being built in 1919. They are a fairly common form of construction – they were built by Councils in large estates as they were fairly cheap and quick to build.

We have surveyed many Laing Easiforms in both Bristol and Gloucester. These dwellings can be identified by their tall slender chimney. The chimney tends to protrude from the central wall; however these chimneys often suffer from failure of the render and tend to crack. Laing Easiforms normally have a concrete porch roof above the front door. But the main way to confirm is by entering the loft space and looking at the party wall.This is not made of brick and block as in traditionally constructed houses, but is fairly smooth and grey in appearance.

How were they built?

Surveying these types of property can be a very satisfying experience as they were all constructed in a very similar way. A solid slab foundation was laid, then a mastic asphalt floor covering which acted as a damp proof course. After the floor was dry, metal shuttering was temporarily constructed and concrete was poured into this mould. This was strengthened with reinforcing bars. As these houses are not constructed from panels brought in from elsewhere, and the work is carried out on site, these are called in-situ. Once the concrete walls were in place, the shuttering was removed and the roof could be added. Normally a traditional cut-type roof was used with some bolted trusses to add strength, for instance those found in Brentry. A flat thick roof comprising a concrete slab was sometimes used, such as in Lockleaze.

What are the associated problems?

Laing Easiforms were not considered to be defective under the Housing Act and as a result can be mortgageable. Hence they are one of the few types of non traditional construction where a mortgage may be obtained! But With every rule there are the exceptions and the most common is the pre 1940’s Laing Easiform. Their construction had thinner walls, with 3” of poured in-situ concrete,  a 2” cavity and then a 3” inner skin – which is very thin by any standard. Some of these are still present in Lockleaze in Bristol and these are seldom mortgageable. The post-war properties were of  thicker walled construction, with  3 ½ ” concrete, a 2” cavity and a 3 ½” inner wall,  such as many of those found in Bishopsworth.

When we survey a Laing Easiform, one of the obvious problems is corrosion of the embedded metal. This is often characterised by horizontal cracking along the reinforcement lines. This may be repaired cost effectively depending on the extent of cracking that is apparent. It is a subjective call as to whether the extent of cracking is cost effective to repair; most suffer some level of cracking.

The other commonly occurring problem is the quantity of asbestos that is often used in the construction.For example, the soffits were originally of asbestos cement boarding, which has often been hidden by new UPVC. The loft hatches were again asbestos boarding, as were the under stairs cupboards. Many of the ducts and boxings-in were also cement type board and thermoplastic tiles were often used to finish the floor.

 

Non Traditional Construction (Part 3)

PRCs, Cornish Type 2

The Cornish Type 2

Unlike the Cornish Type 1 PRC houses that are found all over Bristol, the Type 2 does not have the distinctive mansard hipped roof, clad with vertically hung tiles on the upper floor. It has ‘normal’ vertical walls! Type 2 houses can be found in and around Stoke Gifford. However they are not always recognisable. Both Cornish systems were declared as “defective” under the 1985 Housing Act and many were subsequently ‘repaired’.When Type 2s have been “bricked up” or clad with either brickwork or render finishes, they appear to be of standard Council 1950’s style construction. In their original form, the concrete reinforced panels are larger than those used on the Type 1 Cornish.

Some mortgage lenders are still wary of PRCs; for further information, see www.BritishCouncil of mortgage lenders etc.

 What are the problems with the interiors?

The internal partitions were not always the standard timber studwork expected in traditionally constructed properties. They are often a lot thinner.Partitions are around 120mm thick in a traditional type property, compared to 75mm in the Cornish Type 1. The latter were often made of paramount boards and if opened up have a segmental carboard type structure internally. These were poor sound insulators and very hard to fix things such as pictures to.

Where the property has been ‘bricked up’ (overclad),the  floorboards are often loose around the edges of rooms. The support joists have lost their bearing  on the external walls due to the rebuilding work. Hence where they meet the wall, the ends of the floorboards often are poorly supported and “bounce” as a result.

And most non-traditionally constructed properties of this time contain asbestos. Products oftencontaining asbestos are the soffits, thermoplastic floor tiles and the in-built soil stack. This is not readily visible except where it is peeking through the roof. Also Artex™ ceiling coverings, often as a result of the 1980’s fashion to hide cracked ceilings.

What about the services?

As these types of property are generally in Council/ Local Authority estates, they may not have been updated.  Electrical checks and gas checks are strongly advised. Due to the solid concrete spine wall, the electrical services are often in trunking as opposed to set into the walls.

These houses will most likely have the older lead water service pipes which can pose a health hazard. They are set into the solid floors and can leak unnoticed for prolonged periods of time, often resulting in insurance claim. We have helped progress many of these in the past!

Recent developments

There has been a drive in the last year in South Gloucester by Merlin Housing Association to overclad some of their Cornish type 2 Units. We have acted as Party Wall Surveyors to some of the adjoining owners. The tenants have made very favourable comments with regards to reduced mould growth and decreased fuel bills since the external wall insulation has been installed. The only complaint has been that handrails and satellite dishes have required special fixings to go through the insulation and fix onto the concrete beneath.

We should be well versed in their construction as our Surveyor Jon Holloway and his family live in one!

Non Traditional Construction (Part 2)

PRCs, Cornish Type 1

What’s a PRC?

PRC stands for ‘PreCast Reinforced Concrete’. The drive for more cost-effective ways of building house began before WWll. So a number of ‘system built’ homes were constructed in the Thirties. However, the war caused huge skilled labour shortages along with was a surplus of steel and aluminium production.  As a result, many new varieties of prefabricated concrete (in both pre-cast and in-situ forms), timber framed and steel framed systems emerged. Between 1945 and 1955, around half a million homes were system built. That was about 20% of the new housing stock! And a further three quarters of million between 1955 – 1970.

What’s the problem?

When the panels were cast originally, either off or on site, the metal reinforcements were embedded in the concrete. Concrete is a highly alkaline material and offers protection to the embedded steel.

However the carbon dioxide in the atmosphere,  carbolic acid in rainwater and chlorides in the original concrete can mix. Over time, this can affect the composition of the concrete. The concrete undergoes a chemical change called carbonisation. The metal reinforcements in the panels and supports then become less protected and the metal can corrode. When the metal corrodes it will expand and cause the surrounding concrete to crack and fail. This can be readily seen in concrete fence-posts in gardens which fail and expose the rusted metal reinforcements.

These failings were highlighted in the 1980’s, when such Council housing came onto the private market. This often meant that mortgage companies would refuse to lend on PRC properties. The government then stepped in and many of these systems were declared as “defective” under the 1985 Housing Act.

The government then set up a company to license “repairs” of these properties. This involved stripping out the old concrete and replacing it with brick and blockwork. This was often done whilst the occupants were still in-situ. This type of work was expensive, but it gave the house a PRC Certificate. This enabled mortgage lenders to consider the property as suitable for lending against. It should be noted that if an adjoining property has not been “repaired” this can also be grounds for a lending companies Valuer to refuse a mortgage so look at the neighbouring properties as well.

The Cornish Type 1

One of the most instantly recognisable PRCs is the Cornish Type 1. This has a distinctive mansard hipped roof, clad with vertically hung tiles on the upper floor.A mansard roof has sloping sides, each of which becomes steeper halfway down. The Type 1 looks a bit like a bungalow but withdormer windows around the first floor!

Thirty thousand Cornish 1 & 2 units were constructed in England over a 20 year production run. They were made by the Central Cornwall Concrete & Artificial Stone Co. Many are a distinctive part of the Bristol landscape and they can be seen from Chipping Sodbury to Long Ashton. The Type 1 was particularly common in Brentry, Thornbury,Patchway and also in Little Stoke.

Both Cornish systems were declared as “defective” under the 1985 Housing Act and many were subsequently ‘repaired’.  However, over 30 years after this legislation, we still see many units that are in their original condition, especially in Patchway.

What repairs are usually required?

Common issues are the joints where the soil vent pipe penetrates through the roof covering this is a design issue and normally remedied by better flashing around this joint and is normally noticeable by staining of the ceiling in the Bathroom.

These suffer badly from poor thermal performance of the first floor which can lead to mould growth. The original insulation in the Mansard type roof was notoriously thin at around 25mm in thickness, which is very minimal and if improvements have been made they are often only visible using a thermal imaging camera.

As with most PRC properties asbestos was also used in soffits and floor tiles and roofing of the outbuildings.

 

Asbestos Boarding

 

Asbestos Boarding

Asbestos boarding is one of the harder materials to ascertain visually what type of asbestos may be present.Cement boards (normally white) are often harder and more brittle however this type of intrusive testing must ONLY be carried out by a competent person as this can be very dangerous. Asbestos  boards tend to flex slightly before shearing. With boarding it is essential that tests are carried out as this is one area where the more harmful Blue and Brown fibres can be found.

Externally

During the course of our inspections we often note external boarding on properties that we presume contains asbestos until proven otherwise. Due to its hardwearing nature cement type boarding was often used in soffits very common in properties from the 1950 through to the 1980’s often these have simply been clad with UPVC and only come to light when say the UPVC has been disturbed by adverse weather conditions. Infill panels in walls are also fairly common mainly in 1970’s buildings due to their good fire resisting properties. The age old shed roofing and walls.We have even seen it neatly stacked in sheds or next to fences or hidden out of site as mentioned in our previous blogs. we have also found it cut and shaped as decorative finials externally which would have created a lot of dangerous dust when installed!

Internally

Asbestos sheeting was often used internally for lining loft hatches, creating boxing in and as boarding on walls and ceilings. This type of material is often painted many times in its life so has a simple gloss finish, this makes it harder to recognise you can use a bradawl or Stanley knife to make a small nick in the surface to look at the material beneath.  The other great visual indicator is a dimpled almost golf ball effect that makes it stand out as being a manufactured board as opposed to timber. These boards are often found beneath staircases or making the under stairs cupboard. Where pipes run internally these are often boxed in again sheet material is used.We have also found sheets of asbestos insulating board used to support tanks and cisterns in loft spaces.

What to do

Boarding can be composites of asbestos including the more dangerous blue and brown fibres sometimes called mill boards, that is why it is imperative that when boarding is found and is suspect that it is tested by a competent operative preferably an independent surveyor with no affiliation to removals companies to insure that there is no commercial interest in the findings.

Asbestos Pipework

Asbestos Pipework

Asbestos was often used to strengthen cement based pipework. This pipework performs fairly well as long as it has been regularly decorated throughout its life span. However, where paint has failed the cement based pipework will be exposed and can spall or become porous.

Gutters and downpipes were very often constructed from asbestos cement. The condition of them gives the key to removal, remember they cannot be rubbed down and repainted unlike cast metal gutters if they require decoration.You must not sand or scrape the existing paint from the surface as this can release fibres. They are brittle and if used below ground are susceptible to compression forces causing them to crack although this often cannot be seen. Even when replaced it is unlikely that the ground has been excavated and even where the visible pipework has been removed it is often sealed to a below ground cement pipe which is still asbestos containing.

Soil pipes sometimes called soil stacks are used to take foul water from bathrooms and WC’s .It is easily identified as it should extend above the height of windows or lower roof line and is open at the top (sometimes covered by a cowl) to allow air to enter the stack it is normally wider at around 6” or 150mm in diameter. These can also be cement type pipework.

There are often mushroom shaped cowls extending through walls from where old boilers were located and removed. These are fairly easy to identify as they are often short in length and curl upwards with a domed top and they are highly likely to be asbestos cement.

It is very hard to determine if pipework is cast metal or cement based, especially when it is painted as often the connectors and fixings appear visually the same. With open hoppers curved edges can be a good visual indicator as cast metal is not easy to shape in curves hence if the hopper head is scallop shaped then it is likely to be asbestos cement based. A good way to determine if the pipes are cast metal or cement based is to use a magnet as shown in this video.However with all good tests there is always an exception to the rule and this is zinc guttering which is not magnetic but not asbestos containing.

Often flue pipes to boilers are left inside properties these are likely the most dangerous as they can contain Blue or brown asbestos and should be tested prior to removal.

If you are removing them or employing a trained competent contractor then Health and Safety Executives “Asbestos Essentials” gives an idea of what is required to safely remove these pipes.