Tag Archive for: loft

What about that Loft Space

January 2, 2020/in Our Blog/by holloway

Loft space

In an earlier blog, we’ve already dealt with ‘Loft Rooms’, the conversion (successful or otherwise) of the attic to habitable space. But if this is not a feature of the property you are considering purchasing, you may not be giving much though to the loft space. It seems a minor matter compared to possible structural movement, roof condition, dampness or the presence of asbestos. However, usable loft space is great for storage of those items you only use occasionally, the artificial Christmas tree and decorations, the inflatable swimming pool, the holiday suitcases…

In our reports, we comment on access and boarding in the loft space, as well as the insulation present and the condition of the rafters. For example, “there was no loft ladder, boarding or lighting provision”. This is comment is often skim-read by the client who then files it away for later, or ignores it.

However, on Facebook recently we were asked to comment on the supply and fitting of loft boarding and a loft ladder for £810.00 – was this a good deal?

What are the options?

Boarding

To supply and fit a layer of chipboard flooring, normally we would suggest around £25/m2. This is for smaller areas, say a room where more cuts and noggins and gluing down the overlapping edges will be required. A loft space on a small house can easily be 40m2 then this adds up – say £1000.00.

Loft Ladders

Then you start looking at the many different types of loft ladder – metal or timber, with folding or sliding variants – and the choice starts to become bewildering. Since loft ladders are seldom used even if they are in place, you may forget how to operate them. They can be rather dangerous! Many types drop or slide uncontrollably when you open the loft hatch and hence you risk them hitting you. Some of the locks or catches do not always engage correctly as we know to our peril. One surveyor almost lost his toe when a catch failed on the loft ladder and the guillotine action caused a rather painful few weeks of hobbling around. Cost? From £80 to over £300 for a super deluxe wooden model.

Hatches

Modern loft hatches have draught-proofing and in-built insulation, or may simply be a hinged timber board. We often look around the loft hatches for signs of wood boring insect . These prefer damper timber which is often caused by moisture-laden air escaping around the hatch and condensing on the surfaces. Hence some draught proofing is advisable. Some older loft hatches incorporated asbestos cement sheeting in their construction, hence incurring increased removal costs.

Weight Loading

The other issue is one of weight loading. The TRADA tables suggest that when the roof design is calculated, there are no significant weights in the loft space (the odd plastic Christmas tree aside). However, when the loft is boarded out this will increase the deadload on the ceiling joists, even before we have started to store the seldom-used artefacts. In a RICS building survey at a small house in Clifton, the ceilings were noticeably cracking. The vendor pointed this out to us, saying it was just his luck that as he put his house on the market the ceilings had started to crack. Inspection of the loft void found that in an attempt to clear the habitable areas to make the property look attractive, he had put a huge amount of contents in the loft void. This included a weights bench and set of weights. Needless to say, this had an adverse effect on the ceiling joists below and the plaster attached to them.

So simply boarding the loft can become a rather complex project. The short comment that we use to describe access and boarding in the space may suddenly have a significant cost implication well in excess of that £810.

Non Traditional Construction (Part 1)

January 18, 2018/in Our Blog/by holloway

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.

OH, GOOD, IT ALREADY HAS A NEW ROOF…

August 3, 2017/in Our Blog/by holloway

roof

So you have diligently used our blog entries to guide you in viewing a property. You can see concrete tiles and the estate agent has said‘ Don’t worry, it has a new roof!’ Why should you be concerned?! Half of the ‘new roofs’ we inspect at in the Bristol area should have Building Regulations approvals and do not. Two aspects! First, it’s difficult to sell a property without the correct approvals. Second, the workmanship may not be acceptable if not approved.

As we know,pre 1950’s roofs in Bristol were usually covered with clay tiles (or slates) which were lighter than concrete. Now it has a concrete roof so we know from the planning portal that it is likely to need Building Control approvals. This will ensure the roof structure is strong enough to support the concrete tiles. Also that Fire (Part B) and Energy Performance (Part L) criteria have also been met.

THE STRUCTURAL ISSUE

If it has been re-covered with concrete in the last say 5 years, then very little time will have elapsed. The building’s lifespan is a lot longer than ours! And the faults linked with overloading the property’s roof structure can take years to develop. The existing timbers (the rafters and purlins) may be too thin to support the new heavier tiles. If they have been replaced, these may also be inadequate.

The replacement covering should have been constructed with input from a structural engineer. (S)He would have determined the loadings. He would then have checked that the load bearing walls were suitable for the increased loadings.

If the timbers have been replaced, they may have the stress gradings stamped on them. This shows the strength of the actual timbers. C16 is weaker or C24 is stronger. The trada tables then give allowable spans depending on the centres.

Why does this matter? First the rafters will bow, causing the load(weight) of the roof to be sent at an angle into the walls. However, the load should besent vertically straight down to the foundations. This often leads to cracking around the tops of the walls, commonly known as roof spread. This can be seriously expensive to repair.

Eventually the roof itself will deflect and the tiles become loose… look at the ridge line carefully!

WHY WOULD YOU SPEND SO MUCH MONEY AND NOT HAVE THE WORK APPROVED?

It is not normally the vendor’s fault! Roofing works are very expensive so it is likely that the cheaper quotes were accepted. From the roofing contractor’s perspective,it does make life easier not to inform Building Control! Awaiting Building Control inspections can delay payments and hold jobs up. And if the work is not inspected, the contractor would not be held liable for infringements at the time.

It is likely that this missing compliance “paper trail” is only identified when selling the house.It normally comes as quite a shock to the vendor! Indemnities are often offered by the solicitor but thesemerely indemnify against enforcement action being taken by Planning or Building Control. They do not deal with the quality of the structure in any way.

HOW CAN YOU TELL?

There’s a very quick trade secret ! If the has been recently recovered and has less than 270mm of loft insulation present, then it would not comply and hence we know has most likely not been inspected. Otherwise, ask the vendor about the Building Control sign-off documentation. If that is not present, make sure your surveyor inspects the roof structure thoroughly, which won’t happen in a home-buyer’s report !

Lofts and Attics

March 17, 2017/in Our Blog/by holloway

Lofts and Attics

Loft spaces

You are unlikely to get access to loft spaces when doing a general viewing. It’s easy to put your foot through the ceiling below when you slip on a joist! And this will be on the vendor’s household insurance or agent’s insurance so you would not be popular. So don’t be surprised if the agent will not let you check the loft void. Just smile, knowing we will check it thoroughly for you after you have made your offer.

However, you may be allowed to poke your head and shoulders through the access hatch, as for a homebuyer’s report. Or you may be buying a property privately.

Precautions

Checking lofts is not for the faint hearted as spiders, wasps, mice, flies and rats also make these locations their homes. If you don’t like creepy-crawlies, don’t go exploring in a strange loft!

Some of the older types of loft insulation have been known to contain asbestos. So do be careful and wear a PP3 level mask before opening any loft hatch of an older property. And carry a torch with a long beam, as very few loft areas have lights.

There are three main aspects to consider in loft spaces:

Sarking Felt

Roofing (sarking) felt is designed to keep the roof waterproof, lying beneath the tiles. It should stick out into the gutters.

One of the best easy tests is to simply turn off any torches or lights and look to see if daylight is visible through the roof or eaves. This suggests holes in tiles and felt or detailing (finishing) problems.

If the black bitumen type felt is present, this is a much older felt.If there are large rips or tears present, it may need replacing.This is a very expensive job -say £6k+.Differing colours of felt indicate where patch repairs have been made internally. These are rarely successful and again replacement in probably necessary.

Is the felt white, blue or green coloured, with tiny dimples? This suggests that the roof has been recovered in the last 20 years with a stronger breathable type of felt and should have a long service life left. However, look for rips and tears, due to poor installation. And condensation can still cause mould growth.

Timbers

The main things to look for are split or bowing timbers in a roof structure. Cracked timbers are often very noticeable as the sharp edges and shear nature of cracks tend to draw the eye. Rafters, struts and braces can often be strengthened internally without the need for expensive scaffolds.

Where major components such as purlins have bowed, this is seldom an “easy” fix. It may have been caused by heavier replacement roof tiles, for example. Often a new larger purlin will be required, at considerable expense.

Bowing timbers change the way that load is carried through the building. Bowed purlins and rafters do not transmit straight down at 90° and instead push outwards.This puts additional stress on the masonry. When rafters dish in this manner, it can cause” roof spread”, damaging the supporting walls below.

Keep an eye out for patches where the timbers have clearly been stained by water in the past (or at present!) This is most likely around chimneys, where the flashing above has been damaged. Rot may have already set in.

Insulation

With the ever-increasing cost of heating, loft insulation has been retrofitted in many homes.

Beware! Older types of insulation were vermiculite, gold shiny coloured lightweight pellets and blown cellulose which looks like tiny fragments of newspaper – which is often what they were. These types have been known to contain asbestos. If these are visible, don’t go any further into the loft – be thankful you are wearing a mask!

Sometimes the loft floors have been boarded so it is difficult to add insulation.Modern Building Regulations require 270mm of mineral fibre. This is rarely achieved as the rolls normally come in 100mm thickness so 200mm is more usual.