Practice makes perfect

Serial self-builder Mark Young’s fourth project, an ICF-built family home, has scored so many hits on his family’s wish list that it might be his last project


Back in the November/December 2018 issue of Selfbuilder + Homemaker we spoke to Mark Young about what was then his third self-build. At the time he and his wife Sharon said they weren’t ruling out doing another build, but weren’t planning one anytime soon.

Fast forward a few months, however, and things had changed. Mark still had the building bug, and spotted a site with a dilapidated house on it. “I stumbled across it, and thought long and hard about whether to take it on, because it was such a huge project,” he says. “It’s a large site with an existing property,” making it very different to his last build. 

Despite his reservations, Mark describes it as an “obvious project” and therefore too good an opportunity to resist. Although there was a house on the plot already, renovation was out of the question, for multiple reasons. Firstly was the fact VAT can’t be claimed back on a renovation, but secondly was the poor state of the house. “It was in very poor condition,” explains Mark.  

Although they were clear on wanting a new build, Mark and Sharon were immediately faced with a potentially huge hurdle when the local conservation officer and consequently Natural England were brought in to assess whether the house should be listed. “It was so stressful,” Mark says. “If they had listed it, it would have been a disaster. However, the fact it had not previously been listed was a positive.” 

As well as the back and forth regarding the building’s potential listing, they would endure an arduous planning battle, which ended up taking 18 months. “There were many hurdles,” Mark says. It was during this period that their architect, Jim Hicks of firm Owen Hicks suggested renovating instead, but Mark immediately dismissed the idea: “I told him, ‘we need to fight on’.” They also had a particularly strong-willed neighbour who was so determined to stop them that he hired his own planning consultant, but thankfully it didn’t prove fruitful. “He tried everything, but one person is not enough to derail a justified project,” Mark says. 

Despite the battles and hurdles, Mark and Sharon had to make very few compromises on their initial designs. The only change was the removal of a separate detached office building, which they took out to make it more attractive for planning. “It meant we were replacing a four bed with a four bed – which made their assessment like for like,” he explains. “When you increase scale and bedroom numbers it becomes more difficult.” 

Mark hadn’t used architect Jim Hicks previously but had seen and liked the firm’s modern style. Jim presented the couple with the design he had done for his own house, believing it would work well on their site and fit their main requirements – four ensuite bedrooms, attic trusses, and open plan living. “We made changes externally and internally, but the principal layout he had actually already built himself,” Mark says. 

This made things much easier, giving them a solid starting point which “ticked all the boxes.” One of the changes made was driven by a break in at the site nine months into the project. “We changed the orientation following that, for security,” Mark explains. Thankfully nothing significant was stolen – just a lot of garden items – though he adds that this was certainly “one of the low points” in the build.

Compared to his last project, which was a traditional build with a lot of oak, Mark describes the new house as far more contemporary, in fact it’s “drastically different.” He gives the architect the credit for the design, though he also did his own research, including visiting the National Self Build & Renovation Centre (NSBRC) in Swindon. 

Although the design is decidedly modern, they still made use of stone and timber, to help blend in with nearby listed properties. They discovered through the heritage consultant that the house on the site previously was built of stone, but
had been poorly bricked over. “There was history, but it hadn’t retained any of its original character,” says Mark, which explains why it wasn’t listed.

A large part of their planning application focused on referencing that history and restoring other parts of the site, such as a large pond. They reused all the stone from the old building, and discovered an 18th century stone path under the grass, the slabs from which they plan to use at a later date. Alongside this, they also found there were bats on the site, and had to make provision for them. Mark says it’s “not a major problem – the problem is the cost of all the reports, but sustaining wildlife is rightly given importance.” 

The expense of these ecology reports, along with those entailed in retaining materials and the hassle of having conservation consultants involved means the planning process for this project added up to “a horrendous challenge,” says Mark, “on another level to any of my previous projects.” 


With the planning process finally wrapped up on 7 June 2020, work was ready to begin on demolishing the existing house in July. “It hadn’t been touched for 50 years,” Mark says. Despite the demolition work and cost involved – something Mark hadn’t had to factor in on his previous build – he says the services already running to the site helped balance it out. “Demolition isn’t a major problem; it doesn’t add a huge cost, not if you can reuse the material.” 

Mark chose to use insulated concrete formwork (ICF) to build the house – polystyrene shells filled with concrete – something he hadn’t used previously but is now a big advocate for. “It should be used more. The house is so warm, you don’t need the heating on upstairs.” The insulation values and “relative simplicity” of the construction method were the main selling points for him. 

Mark used an ICF specialist, and while they took care of installation, he project managed the rest of the build, including ordering supplies and arranging subcontractors. “It’s all cost and control,” he says. “You can hire a main contractor but you pay at least 25% more, and I don’t like the idea of having somebody controlling everything.” Having completed three projects previously, he says it’s got easier to manage each one. “You learn what materials you can get, what you can and can’t do,” he explains. “Once you understand what items are available it becomes much easier.” 

There was a slight incident when the concrete escaped in one area when it was being poured. “You have to let it run out then shovel it back in,” Mark explains. “It sounds simple but it’s a lot of work!” There were also complications when pouring concrete for the gable as gravity means it all wants to run to the bottom of the slope. “The gables were the most difficult thing to do,” he says. “We had to rectify some problems there.” 

They also decided they wanted to extend the lounge area after the shell had been constructed, which meant appointing a specialist concrete cutting company – at a “considerable cost” – to move one of the single storey walls. “The density and weight of a 150 mm wall is considerable and requires specialist cutting equipment and telehandlers,” he explains. 

Although annoyances at the time, none of these things caused huge delays – in fact most only a handful of days – and Mark is pleased with the pace at which they got the build done. The house was ready for them to move into in August 2021, with a vast chunk of the build taking place after the initial construction halt caused by the first lockdown, but while Covid was still at a peak. For the self-build, says Mark, “it was perfect, we had staff furloughed and couldn’t meet clients, so we had more time.” He had also taken a risk and ordered the materials a few months prior to planning being granted in April 2020, when there were signs of potential supply issues. “It was a big risk, but it was the right decision!”

He says the budget was “loose,” and admits they went over. One reason was the stonework, which is “very expensive,” Mark admits. They had stone slips, sourced from Black Mountain Quarries, attached in individual layers to the ICF. Being slips, it’s “better for the environment, as it uses less stone, and it’s easier to lay,” he explains. “It looks fantastic, but it’s expensive.” 

The financial challenge meant Mark had to make a sacrifice, and has postponed installation of the air source heat pump; at the moment they are using LPG. “It’s set up so that we can change the boiler to air source, which I definitely will,” he says. The boiler feeds the underfloor heating up and downstairs, and the radiators in the attic space. An MVHR system has, however, been installed; he believes it’s essential for fresh air when building using ICF, as the house is so airtight. A further sustainability move was ensuring doors are triple glazed, installing solar PVs, plus using the original well as a water recycling source.

Mark and Sharon had sold their previous, self-built house prior to beginning work, and spent just under two years living in a mobile home onsite with their two children, aged 19 and 21, from October 2019 until August 2021. “Being confined in the mobile home in lockdown was hard.”


Mark and Sharon knew they wanted the house’s interior to be very contemporary. Wooden and tiled flooring features throughout, and they installed a black, contemporary kitchen. At the centre of the open plan living space is a modern wooden staircase with glass balustrades and lights.

The house is L-shaped, with the longest part downstairs accommodating the large open plan kitchen/dining/living area, plus a separate living room with a vaulted ceiling – another of the architect’s ideas. “The ceiling is one of the nicest bits, it makes the room feel huge,” says Mark. The shorter part of the ‘L’ includes the single storey main entrance and hallway, a utility room, wetroom, double garage, and an additional staircase. “The architect linked the utility and hall to join the garage to the house,” he explains. “It’s a very clever design with a flat roof and overhanging front and back which creates a natural porch.” 

There are also 4.5 m wide sliding doors and full floor-to-ceiling height windows, which Mark says are one of his favourite features. The aluclad doors from Eximia Glazing “give a warmer finish inside.” 

Upstairs houses four substantial double bedrooms, all with their own ensuite bathroom. One of these sits above the double garage, accessed via the additional staircase, and is, says Mark, “effectively like a flat.” While the layout of the last home wasn’t right, this is “much better for our family,” he adds.

When it came to technology, they chose to include Lutron lighting – controllable from their mobile phones – and have ethernet throughout via a central server. They also installed what is a must-have for them having had one in every house, an inbuilt vacuum system – “it should be more popular than it is.”An alarm and full camera is also installed. 

Mark has also learned to spot the various project potholes before he hits them. “You gain experience in every aspect, you know what problems to look out for,” he says. “From digging out to footings to first fix and second fix, even where you haven’t put sockets before where you should.” 

The house sits within 13 acres of land so there’s still a substantial amount of landscaping to do. With the help of a local carpenter, Mark and Sharon have built shepherd’s huts on part of the land which they’ll run as holiday lets. “It’s got a lot of potential, but it’s a big site,” Mark says. He also plans to eventually apply for a triple car port, but says for now “I’ll give the planners a rest!”

Despite his love for self-build, Mark admits it’s “not for the faint-hearted” and the family intend to stay in this house for the foreseeable future – though he doesn’t completely rule out another project one day. “I expect I’ll do one more at some point,” he says. “You need a bit of a rest. To keep doing them back to back would be very stressful, and tiring!”