Regions we cover
LINX Design & Build takes on architecture, planning, extensions, loft conversions, renovations and new builds across Hertfordshire. One in-house team designs each project, secures approval from the relevant district or borough council and builds it, starting with a free survey and a fixed-price quote.
Tell us about your project — we'll come back with next steps and a time for a free survey.
Design & build
Hertfordshire has ten district and borough councils, and much of the county outside its towns is Metropolitan Green Belt, so extensions to rural and edge-of-town homes are judged against the size of the original house. In the west, the Chilterns National Landscape covers the countryside around Tring and Berkhamsted, adding further controls.
The county also contains Letchworth, the world's first garden city, and Welwyn Garden City, where estate management schemes require consent for many external alterations in addition to planning permission, as well as post-war new towns such as Stevenage, Hemel Hempstead and Hatfield. Market towns such as St Albans, Hertford, Ware and Bishop's Stortford have conservation areas with many listed buildings.
Hertfordshire's housing includes Victorian and Edwardian terraces in St Albans, Watford and Hitchin, Arts and Crafts houses in Letchworth and neo-Georgian homes in Welwyn Garden City, interwar semis in Bushey, Watford and Rickmansworth, and post-war new-town neighbourhoods in Stevenage, Hemel Hempstead and Hatfield. Harpenden, Radlett and Berkhamsted have many larger detached houses suited to two-storey and wrap-around extensions, while terraces and semis suit rear dormers, hip-to-gable lofts and kitchen extensions.
Our services
Our architects design for Hertfordshire's garden-city, market-town and Green Belt settings, including the design standards of the Letchworth and Welwyn Garden City estate schemes.
Find out more 02We prepare applications to all ten Hertfordshire councils and, where needed, the separate estate scheme consent in Letchworth or Welwyn Garden City alongside planning permission.
Find out more 03Rear and side-return extensions suit terraces in St Albans and Watford, while detached homes in Harpenden, Radlett and Berkhamsted suit larger single and two-storey extensions.
Find out more 04Hip-to-gable and rear dormer lofts suit interwar semis across the county; in conservation areas, the Chilterns or the garden-city estates, extra consents apply.
Find out more 05We renovate Victorian terraces, Arts and Crafts houses and post-war homes, including listed buildings in the historic market towns where listed building consent is required.
Find out more 06We design and build replacement dwellings and infill homes; in the Green Belt, a replacement house must not be materially larger than the one it replaces, and other new homes are allowed only in limited cases.
Find out morePlanning
How it works
We visit, measure up and talk through what you want to build and what the site allows.
Our in-house team draws the scheme and handles planning or a Lawful Development Certificate, plus Building Regulations.
You get an itemised, fixed price in writing before any work starts.
One team builds it, keeps you updated weekly and hands over with a 10-year structural guarantee.
800+ projects completed since 2017 · 4.9★ from 500+ reviews · See our starting prices
Questions
Often you need two separate approvals. In Letchworth Garden City, the Heritage Foundation's Scheme of Management requires consent for many external alterations, and Welwyn Garden City's Estate Management Scheme works in a similar way, alongside any planning permission from the council. Both towns also have conservation areas, which restrict permitted development. We check which approvals your project needs and prepare the drawings for each.
In most cases, yes. A hip-to-gable conversion with a rear dormer on a semi-detached house can usually be permitted development, provided it adds no more than 50 m³, keeps dormers off the roof slope facing the road and uses similar materials. It needs planning permission in a conservation area or the Chilterns National Landscape, or where permitted development rights have been removed, and in Letchworth or Welwyn Garden City estate consent may also be needed.
Under permitted development, a single-storey rear extension to a terraced house can usually extend 3 m beyond the original rear wall, or up to 6 m through the prior-approval larger home extension scheme, with a maximum height of 4 m. Much of central St Albans is in a conservation area, where side extensions and the larger scheme are not available. St Albans City and District Council can confirm lawfulness with a certificate.
Rather than a standard rate, we give a fixed-price quote after a free survey, because cost depends on the house, its structure, the design and the finish. The quote covers the agreed scope. Factors such as Green Belt design limits, garden-city estate requirements on materials and details, or matching brickwork on an older market-town house, are accounted for in the quote from the start.
Householder planning applications to Hertfordshire's ten councils have an 8-week statutory determination period from validation. Prior approval for a larger rear extension is decided within 42 days. In Letchworth and Welwyn Garden City, estate scheme consent is a separate process that can run in parallel. Green Belt and conservation-area cases may take longer if amendments are needed. We confirm the build programme once all approvals are secured.
We take on projects across Hertfordshire, including St Albans, Harpenden, Watford, Bushey, Radlett, Rickmansworth, Berkhamsted, Tring, Hemel Hempstead, Hertford, Ware, Bishop's Stortford, Hitchin, Letchworth Garden City, Welwyn Garden City and Stevenage. Every project starts with a free survey at your home and a fixed-price quote from our in-house design, planning and build team.