Chris Parsons from Parsons+ Whittley outlines a traditional procurement route. And Ben and Kay Adam-Smith receive their tender returns.
Ben and Kay Adam-Smith are building a family home to Passivhaus standard and have hired architecture firm Parsons + Whittley to design this house. In episode 205, Technical Director Dan Higginbotham explained how the tender package was put together. Now five shortlisted contractors – sourced mainly through recommendation – are quoting for the work.
What is a traditional procurement route?
This is when the architect, working on behalf of the client, produces a comprehensive specification and a highly detailed package of drawings. Potential contractors then use this information to price up the job. The more detail there is, the more realistic the pricing will be (and like for like comparisons then become possible).
The contractors submit only the headline figures
For this tender process the contractors have been asked for the contract sum, how soon they could start and how long they would take to carry out the work.
Chris has also asked for a detailed price specification, although he is aware that the contractors may not produce this (perhaps because they’ve priced it in a different way and can’t easily produce the document).
However Chris says: “The sceptic in me thinks that by holding it back, if they get a telephone call from me today asking for their price specification, they get an early indication that they’re in the running.”
A code of practice governs this process
In order to make this fair, a procedure is laid down of how to invite and receive tenders, what must be done once they are opened and how errors might be adjusted, etc.
On top of this, a company’s professional reputation would be at stake should any foul play go on!
Everything remains confidential until the contract is awarded
The client will generally be the one to open the envelopes (again, to see that everything is above board).
All these numbers will be kept confidential until one contractor has been engaged.
Only then will the figures be released, so as to give the contractors feedback on their pricing.
Ben and Kay’s tender returns
After waiting for the clock to strike midday, Kay opened the returns that had come in.
The budget of £400,000 was quickly blown out of the water!
Contractor 1 – £612,234 (39 weeks)
Contractor 2 – £885,871 (35 weeks)
Contractor 3 – £744,385 (35 weeks)
Contractor 4 – withdrew due to family illness
Contractor 5 – disqualified (submitted a day late; £664,000)
Some contractors may drop out
Despite working hard to make sure the contractors were a good fit and wanted to price the job, one still withdrew.
And another had to be disqualified after it arrived late.
Chris commented: “I’m pleased that we had a reasonable sized list, so we were not left with limited choice.”
Next steps
Look at Contractor 1’s pricing in more detail and explore what savings can be made through value engineering.
Lucy Pedler, architect and founder of The Green Register, talks about the importance of good communication throughout a self-build project.
Interview with Lucy Pedler
As a child, Lucy was interested in the worlds of science and arts and wanted a profession that could combine the two. She qualified 35 years ago, and has worked as an architect in the UK and US.
Influenced by her father, an environmentalist, Lucy wanted her career to encompass both architectural and environmental work. In the early ‘90s, she worked as a Product Specialist at Construction Resources (the UK’s first Ecological Building Centre) for five years; this involved researching the environmental impact of building materials and systems, and training other construction professionals in green building.
In 2000, Lucy launched The Green Register, a not-for-profit organisation providing independent training and promoting sustainable building practices across the construction industry.
Poor communication is the cause of many problems
Lucy believes we spend quite a lot of time as human beings not saying what we think! If you can communicate effectively – using a bit of tact and choosing words carefully – people know where they stand. Lucy says some people think she’s quite direct but at least there’s no grey area.
Making the importance of communication clear from the start helps to create an environment where everybody’s comfortable talking about the build.
A robust brief ensures everyone’s on the same page
Good communication is key to making the project a success and this begins with a detailed brief. To produce one, the architect or designer must first thoroughly understand what the client wants.
This document should then be referred to throughout the build process as things inevitably change. For example, there may be planning issues, unexpected problems on site, or design alterations. A detailed brief aids important discussions about the time, cost and design implications of changes.
It’s worth spending time setting the green agenda
When people tell Lucy they want a ‘low energy house’ she needs to clarify exactly what that means. Clients may just want low energy bills, or they may have concerns about the bigger picture: the way the house is built, materials used, internal environment, wellbeing, etc. It’s a lot of work that has to be done at the beginning, but Lucy says you’ll reap the benefits throughout the process.
Be realistic about the budget from the outset
A fabric first approach is much better in terms of environmental issues and impact. But Lucy understands that the majority of people don’t have the money to do 100% sustainable buildings, commenting, “Don’t beat yourself up if you haven’t got the perfect house because whatever you do is going to be better than the average house in the UK, which is very, very mediocre.”
Lucy advises people to be honest about access to funds and what you have upfront. Then everybody involved knows what you can afford. You don’t want to run out of money and work to suddenly stop onsite.
The project lead should manage expectations about cost
During a career spanning more than 30 years, Lucy can’t remember a project where the cost didn’t change, usually in an upward direction. Managing clients’ expectations won’t make the problem go away, but lessens their disappointment.
The architect (or lead) should explain the process and set expectations that the project will probably go over cost and time. If unexpected costs arise, they’ll refer back to the brief so the client can decide whether to increase the budget or save costs elsewhere. Lucy says self-builders often see the long-term benefits of increasing the budget.
There’s huge value in face-to-face communication
Modern communication technology sets expectations that everything can be done immediately. While some decisions are quick to make, Lucy thinks we’ve lost something in not being given the time to consider things.
Projects can be discussed remotely using phone, Skype and email, but Lucy gives reasons why talking to clients in person can be advantageous:
You can sketch over plans while talking through concepts.
It’s easier to compare room sizes on plans with the room you’re all sitting in.
Some decisions take a bit of time and are best explained face-to-face.
You can observe non-verbal reactions, e.g. facial expressions.
3D modelling makes it easier to convey concepts
Many clients can’t understand 2D drawings and Lucy comments, “Why should they? It took us seven years of training to get where we are.” She recommends a programme called SketchUp, which is very simple and can quickly produce a 3D walkthrough to use with clients, helping them to experience light and height and changes in space, etc.
It’s important that concepts aren’t presented as a fait accompli, and Lucy says clients should feel able to give feedback. Reviewing conceptual designs is a key stage for communication, when you’ll work out basics such as the position of the living room or the size of the kitchen.
Design iterations take time and can be costly
Lucy recalls a client who requested ten different designs for a 2m x 2m bathroom and chose the original one in the end! A helpful approach is for the architect or designer to state upfront the number of design options included in their price, and make it clear they’ll have to start charging extra for any additional major changes.
A collaborative design and build approach is worth considering
While in the States, Lucy worked with contractors from the conceptual stage onwards and the contractor would inform some of the technical decisions. This approach required a high level of trust, but meant shared ownership of the project. And when it came to pricing the job, the cost was quite realistic.
Lucy says when you go out to competitive tender, contractors may not have understood the drawings or might not be pricing accurately. She cautions, “Although it might appear initially to be the lowest cost, at the end they’re clawing back what they need in order to make a profit.”
A neutral third person can mediate between client and contractor
Lucy says if clients can afford to appoint someone to oversee the project that’s a real plus. The architect or project manager can tell them early on what’s likely to happen during the construction stage and clarify what their fee will cover.
Self-builders often get much more involved, but Lucy suggests clients don’t take on the project management role themselves as they’re too close to the project and usually don’t have the experience needed.
Agree a schedule of meetings for the build
When the construction stage begins, you’re introducing a lot more people, so communication can be challenging. And clients often perceive progress to be slow and see costs increase and timescales slip during this stage.
It’s helpful to plan a schedule of meetings and clarify to the whole project team where they’ll be held, who does/doesn’t need to attend, what’s going to be covered, etc.
Lucy says the one group of people they find very difficult to get into Green Register seminars are builders. She recommends ‘toolbox talks’ if you’re trying to achieve a low energy building, as spending just a few hours explaining the concepts is money well spent.
3 more tips for a successful self-build
The amount of information and decision-making can be overwhelming. Decide how involved you want to be, e.g. technical decisions may be best left to professionals trained to deal with them.
It’s important no one in the team holds back. The client, architect or contractor needs to share their concerns or say if there’s something they have doubts about.
The Green Register encourages post-occupancy monitoring (e.g. of airtightness, fuel costs, etc.). This can reassure you that you’ve got what you set out to achieve.
Paul Testa from Paul Testa Architecture talks about how to predict the costs of a house build and shares his tips on limiting a self-build budget.
Interview with Paul Testa
Architect Paul Testa’s interest in construction led to coordinating and teaching the technology course for the MArch in Architecture at Sheffield University. He’s also a tutor and lecturer for the Sustainable Architectural Studies Masters course at Sheffield University. He is a member of AECB (Association for Environment Conscious Building).
Build cost is not necessarily ‘cost per square metre’
Paul aims to help clients gain realistic expectations of their project’s costs. They start by assuming a mid-range, bespoke new-build would cost roughly £1500 a square metre. They then use their cost calculator to add in additional costs, taking into account factors like slope of the site, higher specification and external works.
To price the whole project, Paul says self-builders should include connecting utilities, landscaping, and contingency in the overall build cost. If an architect or builder prices your project at £1500 a square metre, remember this may not include all the costs of the build.
A steeply sloping site
Fees are affected by more than just project size
It is important to have accurate cost predictions for your build and these do not just relate to square metres. Paul explains that the cost of consultants isn’t tied to the size so much as the complexity of the project.
Some costs, such as surveys, might depend on both the size and the complexity of the project. Paul recommends adding 30% to your construction cost for planning and building regulations fees and any other costs. Some of these don’t change with the size of the build, so the fee will be a greater percentage of the build cost for a smaller project.
Utility costs can vary from site to site
Paul has found the cost of connecting gas to be quite consistent, but not so for the electricity supply. The cost can vary hugely depending on the work involved in making your connection, and remains unknown until the application is made. Furthermore, Paul warns that there is no room for negotiation, saying, “It’s a captive market unfortunately.”
“Most contractors won’t have sufficient insurance for the whole project”
Contractors will have insurance to cover their liabilities (public liability and employer’s liability insurance) and potentially for their equipment on site. The architect also needs professional indemnity insurance and public liability insurance to cover the implications of design decisions. Paul advises clients to procure insurance to cover the new building and materials.
Claiming back VAT may depend on your contractor
Some contractors don’t pass on the cost of VAT: the client never sees that cost and the contractor just claims it as part of their quarterly VAT payments. This may be beneficial for clients who don’t have the cash flow to pay upfront for the build plus VAT and then reclaim the VAT later.
Often clients prefer to procure large single ticket items (e.g. windows) themselves, to avoid the contractor’s overheads and profit. In that case, Paul reminds clients they should budget to cover that VAT cost until the end of the project.
Keep back at least 5% of your budget as contingency
To deal with unknowns such as the ground and weather, Paul recommends having “something there to cover you, a minimum of 5% but more generously 10%”.
He warns that stretching both construction budget and contingency “can be quite dangerous.” He advises spending more at the end if you have money left, rather than pushing to do absolutely everything without compromise.
Expert advice during planning helps predict cost more accurately
Although he cannot completely mitigate the risks of unknown costs, Paul ensures that the correct investigations are done as early as possible to try and minimise additional costs. “Certainly on the bigger jobs where there is more scope for value engineering,” he says, “we will try and bring a quantity surveyor or an estimator in at roughly the planning stage.”
This expert can give a budget cost for the build. If it doesn’t fit within a client’s budget, Paul’s team can make changes before the planning application is submitted, avoiding later amendments and resubmissions.
Avoiding the tender process can actually save money
Ideally, Paul likes to find a contractor he wants to work with and that the client is happy with, who will “buy into” achieving the building at the budgeted price. He relies on the expertise of the chosen contractor to ensure that the detailed design matches that budget.
Although Paul acknowledges the benefits and drawbacks of both routes, he doesn’t believe the tender process is the best way of procuring a building, saying “We actually incentivise that in our fees and we charge less for a negotiated price with a contractor than we would do for dealing with a full tender process.”
Contractor availability can be as important as cost
Paul works with a pool of preferred builders, although this can change over time. He explains that the best contractors can be booked up to two years in advance. Although clients might be disappointed by delays, they usually come round. “If they want the very best product, they want the very best people to do that,” he says.
Engaging the contractor earlier in the process can mean that delays are avoided. Having agreed an approximate start date with a contractor, Paul stays in touch while developing drawings, maintaining agreement on budget and timescales. He says, “By the time we’re ready and the contractor’s ready, everything’s drawing together.” However, he adds, “it doesn’t always work that perfectly.”
Tender processes have their own drawbacks. A four to six week process can lead on to reviewing prices, interviews, and value engineering. After all this, the contractor’s availability might be delayed another year. It can be difficult for a client to ignore a much cheaper quote but Paul warns, “Normally, if it’s too good to be true, it probably is.” The project ends up costing as much but with extra difficulties.
A passive house can be built for less than £50,000!
In 2013 Paul’s team submitted a design to the National Self-Build and Custom Build Association’s annual competition ‘Self-build on a Shoestring’. The brief asked for a detached family home, on a very simple flat plot, for £50,000 or less, including all materials and specialist labour but assuming utility connections were already in place.
Paul’s approach was to make “a simple construction that can be built by the average self-builder”. While mainly a “materials only” cost, it included specialist input such as commissioning the MVHR system, certifying the electrics, gas installation and digger and scaffolding hire.
Not only did their design offer a 70m2 family home for around £45,000, it was also designed using the passive house planning package. Paul says, “We delivered a building that achieved passive house for less than £50,000 and would be a compact but very comfortable single family home.”
Delivering build elements constructed off-site to manage costs and time on a steep site
Five top tips to keep build costs to £50,000
Remove main contractor: get hands on, do physical work, and do your own project management
Reduce risk by choosing a manageable construction method, such as a simple softwood timber frame.
Minimise the number of materials.
Maximise the function of each element, e.g. exploit oriented strand board (OSB) in three ways: as an airtight layer, internal wall linings and structurally, to stop the building twisting.
Choose larger format materials with cheaper production and installation costs, such as fibre cement slates rather than timber cladding.
Ben Adam-Smith explains how he and his wife have been specifying their new home (which will be built to Passivhaus standard).
Ben looks at the decisions that they have made themselves and those which have been dished out to the team.
Decide how involved you want to be
This is a decision that you have to make right at the start when you select your build route. My wife and I opted for the contractor route, which should be the easiest but also the most expensive.
For us, the essence has been on having a good experience because we have a young family and our time is precious enough as it is.
That said, there are still plenty of decisions to be made!
Be guided by the best team you can afford
While we have made lots of decisions on this project there are also many which we have delegated.
There is no way we would have the confidence to do this unless we believed in our team.
This started with hiring the right architecture firm but has also included other specialists (such as an interior designer, M&E engineer, and garden designer).
We always aim to understand why decisions have been made but there have been a few times where it’s got too technical!
Tender documents need detail to be meaningful
If your build route will see you go out to tender to a small number of builders, then you will need to make as many decisions upfront as you possibly can.
It is possible to say things like ‘allow £3000 for a bathroom’ but there’s more risk doing this than if you choose your bathroom products and materials, get them priced up and then don’t change your mind.
A house can be broken down into its constituent parts
Specifying a house is a huge task for a first-timer, so it can be broken down into manageable chunks.
For example, the headings might include structural system, electrics, mechanical and plumbing systems, the internal and external doors, the windows, floor finishes, etc.
You can then go into another level of detail. So for electrics, that might consider the numbers and positions of light fittings, light switches, socket outlets, telephone points, ethernet and data points, smart systems, TV, alarm and so on.
Clear your diary during the technical design phase!
Self builds do not progress in a linear fashion. There are fits and starts. Specification is definitely one of these.
Once our architects were focusing on this stage, they moved quickly.
Kay was really good a responding to emails in a timely manner and trying to bat the ball back into their court.
Watch Mike Coe’s video
Former ITV News cameraman Mike Coe is embarking on his second self build in Portree, Scotland.
This time around he’s going to be providing regular video reports on his project progress.
However, his first report looks at why he and his partner Lizzie decided to leave their ground-breaking autonomous house to move further north.
The answer is comprehensive to say the least . . . and has turned into a 50-minute documentary! It sums up problems with UK house-building and why the issue of climate change is not being tackled adequately.
Ben and Kay Adam-Smith have a difference in opinion over which windows to specify for their new build Passivhaus home. While Ben is keen to minimise mullions, transoms and window frames, Kay believes this takes away from the aesthetics of the building.
A visualisation of Ben and Kay’s house
Today’s episode is really a short story about aesthetics. Life would be boring if we all liked the same thing. However, what happens when you’re working with your other half on a self build and you strongly disagree about something? How do you move on? Well we haven’t answered that one yet, but we can share the disagreement and let you know what happens over the course of time!
I (Ben) also feel like I might have said what my wife is saying a few years ago. I believe I’ve grown in my understanding since then and so now my opinion has changed.
Mullions, transoms and window frames
Firstly what are mullions and transoms? Well, they are the structural elements that divide up sections of a window. Mullions are vertical while transoms are horizontal.
There’s no denying that the use of mullions and transoms can make some beautiful windows (as in the stained glass window above, where it’s taken to an extreme).
In the past it was just not possible to manufacture large single pieces of glass and so to achieve a big window, a number of small ones needed to be ‘stitched’ together.
Large glazing is now possible
Probably a window’s most important function is to provide that visibility from one side to the other.
Windows without mullions and transoms therefore do a better job of connecting the inside to the outside (and obviously bring in more light).
As we spend 90% of our time indoors, you could argue that the view out is more important than the aesthetic appearance of the window from the outside.
Large single pane windows are still not the norm
In a country where our period properties make up a large proportion of the housing we live in today, it is hardly surprising that we gravitate towards their features.
That’s perhaps why Kay would like two of three ‘lights’ (subdivisions) in each window.
She also thinks that a lot of houses that use large panes of glass just don’t look right; they look like they need to be sub-divided.
Reducing the amount of glazing in a window affects its performance
The frame is generally the weak point of the window.
Chris Parsons of Parsons + Whittley says: “We want more glass and less frame in the way, because the more glass we have the better the performance of the window. When you start dividing them up with mullions and transoms, you now can’t insulate that part of the frame by wrapping anything around it.”
How much glass is actually in a window?
PHPP models the amount of glass and the amount of frame
Even if a window has a good central pane U-value (a measure of how effective it is as an insulator), it is only referring to the glass. Therefore the Passive House Planning Package (PHPP) requires information on both the amount of glass and the amount of frame in every window. This is the only way to produce an accurate model of the thermal performance.
The ease of opening and closing windows depends of their size
While performance is important when creating a Passivhaus, it must also be balanced with practicality.
When windows get too big, they take a bit more manoeuvring so this could become a valid reason for introducing different lights in certain windows.
Aesthetics will always be a key driver in window choice
There is no doubt that windows with mullions and transoms produce a pretty pattern on the window.
It is also possible to get Passivhaus sash windows, for example. However, for new build, does it make sense to specify sash windows (given all the arguments above)?
This is a choice you’ll have to make . . . and a choice we have to make on our build!
Keep an open mind
This can be a great attitude to anything in life and it’s just the same with architecture.
