Ab.ovo Structural Engineers

08/12/2024

Very occasionally, we get to do some work on our own property! After 23 years of putting up with a too-cramped kitchen and utility room, the decision was taken to take out the latter and combine it into the former (plus new kitchen and flooring). This in turn gave rise to the opportunity to remove the door and window to create a single large opening for a set of sliders; eventually, these will lead onto a rebuilt raised deck area, enabling al fresco dining on those balmy days…remember them?!

Just like everyone else, we have to have Building Regulations approval for structural work, necessitating the provision of calculations, in this case for a new lintel spanning across both openings. The simple way of designing it would have resulted in the need for a heavy duty lintel, but the alternative (and more protracted!) way of designing to BS5977 allowed the use of a standard lintel instead, for lesser cost.

The bricks are all reclaimed from the original soldier coursing (these were removed to install the temporary props and new lintel) and from below the original window opening. The left hand side jamb below the window has been carefully rebuilt, rather than merely being disc-cut. It is a testimony to the skill of our builder that it is hard to tell that this opening is not actually part of the original structure.

06/10/2024

**The Building Safety Act 2022 [BSA]: a seismic change in the construction industry**

As a result of the enquiry into the 2017 Grenfell tragedy, the BSA was introduced in October 2023 and came fully into force for England in April 2024. It creates a new class of residential building known as Higher Risk Building (HRB), for which additional measures will apply, but will apply to *all* residential buildings.

This Act confers responsibilities for managing building safety risks upon everyone involved in a building project, to ensure insofar as is practicable, compliance with the Building Regulations. This includes the building clients/owners, who are required to appoint a Principal Contractor and Principal Designer.

For a non-domestic property/client, if the client fails to appoint, then the responsibility for undertaking duties in those positions automatically passes to the client.

With regard to a domestic property, if the client is a domestic client and fails to appoint, then the main/sole contractor will automatically assume the duties of Principal/Sole Contractor and the main/sole designer will become Principal/Sole Designer. If, however, the property is related in any way to a business, that is it is either owned by a company, is a BTL/HMO/Airbnb property, or a business is run from those premises, then failure to appoint will be treated as for a non-domestic property and the client will automatically take on those duties.

Where we are involved with a domestic project, Abovo will often be the sole designer: such an example would be for a simple knock-through project, where there is no architect involved. Providing that the work does not have any impact on other parts of Building Regulations, for example means of escape from fire, then we will be happy to assume the duties of Principal/Sole Designer under the BSA.

However, if for example, you are planning a loft conversion, this can have an impact on means of escape, electrics, plumbing, stairs, heat loss and others. In these instances, in keeping with other structural engineers, we will not generally agree to act as Principal Designer.

The reason for this is that, as part of obtaining a completion certificate for the works, we are required to sign documentation to certify that the works comply with *all relevant* Building Regulations, much of which lies outside our normal remit.

We will expect that in such circumstances, the homeowner will appoint a qualified architect or technologist (or other suitably experienced and qualified person), who will take on the role and we will then act as a Designer under the aegis of the Act.

This does not necessarily preclude our carrying out design work before a Principal Designer is appointed. However, our calculations and drawings will be marked as not for Building Regulations submission and approval, until such time as the appointment is confirmed.

What the BSA will bring about is the end of unqualified/uninsured people carrying out design work as 'private jobs', once people fully appreciate the degree (and longevity) of risk that attaches to design work under the BSA. Also, there are already some local authority Building Control departments who are refusing to accept calculations and details which are not on headed paper/drawing sheets from bonafide companies and/or sole professionals.

Obviously, from our point of view, this will level the playing field in respect of ensuring that we only compete for business against similarly qualified and insured professionals, but there is also the intended consequence of a higher, safer standard of construction, which is to the benefit of us all.

Further and (much!) more detailed information regarding the Building Safety Act 2022 can be found at https://www.gov.uk/guidance/the-building-safety-act and https://www.legislation.gov.uk/ukpga/2022/30/contents #:~:text=Building%20Safety%20Act%202022%20is%20up%20to%20date

Building Safety Act 2022 is up to date with all changes known to be in force on or before 06 October 2024. There are changes that may be brought into force at a future date.

06/07/2022

A recent addition to the Abovo drone stable, along with the Mavic Air 2 and Air 2S, is this excellent feat of miniature engineering and electronics, the Mini 3 Pro.

This tiny marvel weighs in at just under 250g, meaning that there are significantly less controls over where it can be flown and how close to people it can go. It is particularly useful on surveys in built-up areas, where we would otherwise have to get the permission of neighbours within 50m, before we could - legally - carry out a survey inspection of a specific property.

If there is something that needs inspecting, without incurring the expense of constructing scaffold or tower access, or even if if it’s simply too dangerous to access by normal means, the various drones that we run can produce high quality video footage and photographs.

Although not a strand that we actively promote, we do also carry out drone inspections for third parties. We don’t do weddings, though: they’re far too stressful!

28/05/2022

This being Norfolk and the fact that there aren't that many of us about anyway, we structural engineers will generally try and help each other out where we can. And so it was that we came to carry out a drone survey of Pinebanks Folly, for one of our fellow firms of local consultants.

An inspection of a parapet to a tower on the side of the folly was required, so that the scope of any remedial works that might be determined. Physical access would require crossing a flat roof with no perimeter barrier and so mitigation would be required in the form of harnesses; this in turn would require the installation of suitable support points and the derivation of an escape plan, in the event of the unthinkable happening.

All of this would both time consuming and expensive. And then there is the issue of finding a member of staff willing to carry out the inspection! By comparison, a drone survey is usually relatively straightforward, the risks are greatly reduced, it is generally quicker and easier to arrange and the cost is considerably cheaper.

We were able to fly to the structure from an off-site location (after liaising with security for the site) and carry out close-up inspection of the area of interest, taking both photographic and video records; shooting the photographs in RAW format means that we can carry out much more detailed processing of the photos in Lightroom/Photoshop and the videos are shot in 4k to give excellent resolution.

At the end of the survey, we carried out a little fly-around of the structure, just for a general record of the structure as it stands (and our own amusement!).

We invested in obtaining drone operation and flight training, as well as formal qualifications, primarily for use with our own projects, but as others have become aware of our capabilities in this area, we are finding that requests to carry out third party surveys are gaining momentum.

This inspection was carried out using a DJI Air 2S drone, a recent addition to the Abovo drone family!

What3Words location for the Folly is cake.curvy.spill

19/05/2022

With significant changes to Building Regulations Parts F and L and the introduction of a new Part O taking place on 15th June, we are seeing several potential clients becoming concerned regarding turnaround time for the structural design aspect of their project before that date.

Our current extremely high levels of workload mean that new projects that we are receiving the go ahead for now are unlikely to be completed before 15th June.

However, to be considered under the current Building Regulations, a submission merely has to be be *submitted*, either under Full Plans or Building Notice, by 15th June 2022. It is important to note that it *does not have to be approved* by that date.

A scheme submitted prior to, but not approved by, 15th June 2022 has until 15th June 2023 to commence on site. Again, it does not have to be *completed* by that date.

A submission can be made without all the structural information being included at the time of submission: this can follow on. The important thing is to have the submission registered with the local authority by 15th June 2022.

Further information may be found on the Government website at https://www.gov.uk/government/publications/building-regulations-in-england-circular-012022.

Building Regulations in England - circular and letter withdrawing and replacing Approved Documents F2, L1, L2, O and S (2021 editions), setting out corrections and amendments.

31/03/2022

We know the importance of trying to minimise our carbon footprint on the planet, both in our professional and personal lives, as much as possible. With that in mind, in May 2021 we ditched the fossil-fuelled vehicle for a BEV, which is powered by 100% (or so we’re told) green electricity via an Octopus Energy EV tariff.

Even with the recent ridiculous hikes in energy costs - with the promise of yet more to come - careful timing of charging on cheap rate means that the “fuel” cost of running the car is still well under 2p/mile. This means that we are able to swallow mileage charges for most of our projects and clients can rest assured that by instructing us to come to site, they are not indirectly contributing to the CO2 in the atmosphere. So that’s a win for us, a win for the clients *and* a win for this little planet that we all call home!

16/03/2022

A fun time has recently been had 3D modelling and designing a barrel roof for an extremely large dormer window within a new-build property, which is also required to support the main pitched roof along its curved (in two directions) inner edge. This will all be formed using steel box sections with fully welded connections, except for along one curved member, which will allow the assembly to be transported to site in two parts and bolted together before being craned into place. The whole assembly is approximately 7.3m x 5m on plan and 1.5m high. It weighs approximately 1.5 tonnes – and not one part of it will be visible when the property is finished.

This is one of two barrel roof dormers for the property. Of course, thanks to the architect, they aren’t the same, which means the whole design and detail process will have to be repeated.

11/03/2022

*SPRAY FOAM LOFT INSULATION*

With the recent huge increases in fuel costs and the promise of yet more pain to come, it is understandable that most people will be extremely conscious of their home heating bills and be looking for ways to enhance the levels of insulation in their houses to mitigate those increases.

As a result of your research, you may come across Spray Foam Insulation (SFI), which often goes under the trade name of Icynene or Renotherm; or you may be door-stepped by someone extolling the virtues of this wunder-insulation.

SFI can be either open-cell or close-cell type and is considerably more expensive than other forms of insulation, such as fibreglass, wool, or mineral fibre. It will typically be offered for around £25 – 50 per m² and possibly you will be told that the company can reclaim £1000 from the government, through a (defunct) grant system so they are able to offer it to you for the “ab-sol-utely amazing sum of £4000”….provided that you sign up there and then, of course. They will often ask for a sizeable and immediate deposit, as well. They may tell you that you that they have calculated you are currently losing 40% of your heat through the loft; and they will be able to tell you this just from a perfunctory look in the roofspace, without knowledge of the extent of any other insulation that the building may or may not have, such as wall or floor insulation, or without carrying out any complicated heat loss calculations. All this by mental arithmetic, no calculator or computer required.

Regardless of the snake-oil salesman claims, whether it is open- or closed-cell makes little difference: it is VERY BAD NEWS for loft spaces. There are potential health issues, as harmful fumes are given off during installation which can linger for a long time afterwards and can affect people with respiratory issues. It seals the roofspace, which can lead to issues with condensation and sweating of the timbers. It prevents inspection of the timbers. The hard setting of closed-cell foam can induce additional stresses into structural timbers. It is a fire hazard, releasing cyanide gas as it burns. Removal is nigh-on impossible.

For all these reasons, building professionals and mortgage/equity release lenders view the existence of SIF within a loft space with understandable concern. If you are selling, the presence of this material is likely to significantly reduce the value of your property. If we notice the existence of SFI during the course of a structural engineering inspection of a property, we will always flag this in our report and state that we are unable to advise with regard to the structural condition of rafters encapsulated by this insulation. This comment, together with any adverse comments that the valuer/surveyor may also have made will be enough for most lenders to decline to accept a property for mortgage purposes.

If you are door-stepped or cold-called by anyone offering to install SFI, thankfully you do have certain safeguards: as the cost of work will be more than £42, you have the right to a 14 day cooling-off period and the right to cancel the contract and obtain a refund of any monies paid over. The salesman should have provided you with written confirmation of your right to cancel when you agreed the contract and, if not, will have committed a criminal offence and you are not bound by any contract. If you have been taken in by the slithery charm of the snake-oil salesman, you should contact your local trading standards office as soon as possible, for further advice.

In short, don’t use this to insulate your loft and ALWAYS OBTAIN PROFESSIONAL ADVICE REGARDING WORK TO YOUR PROPERTY.

08/03/2022

Wishing peace for Ukraine and an end to the atrocities.
Stand with Ukraine.

24/02/2022

The types of work that we get are many and varied. Last week, we completed a commission to certify a steel lifting frame which had been designed by a client. This frame is required to carry 2 Tonnes of bagged powder delivered via an electric crane which runs to hoppers at either end, where it is discharged into silos. We modelled this using a 3D structural analysis program and, with just a few tweaks, were able to confirm that what the client had proposed - and was in the process of constructing - was structurally adequate, to their great relief!