What is Custom Build?
Unlocking land value through the structured delivery of multiplot developments of
Self Build Homes.
With extensive experience at the forefront of the UK Custom Build sector, we support landowners and developers in shaping feasibility studies, design strategies, planning pathways and the delivery of successful multi‑plot self‑build sites.
Custom Build developments can take many forms, depending on the motivations of the developer and the requirements set by the Local Planning Authority (LPA). At their core, these sites enable the creation of multi‑plot schemes for Self Build housing. A well-prepared design code, planning strategy and valuation approach should allow for a broad scope of individual design expression while maintaining the parameters needed to ensure consistency, quality and market appeal across the whole development.
To support this, sites often include concept house types, providing an agreed reference point for architectural style and design intent. These concepts offer assurance to the landowner or developer, the LPA and future plot purchasers that all homes will be delivered within a clearly understood and mutually recognised framework. These designs should allow for extensive customisation.
"In considering whether a home is a self-build or custom build home, relevant authorities must be satisfied that the initial owner of the home will have primary input into its final design and layout.
Off-plan housing, homes purchased at the plan stage prior to construction and without input into the design and layout from the buyer, are not considered to meet the definition of self-build and custom housing." - Self-build and Custom Housebuilding Act 2015 (as amended by the Housing and Planning Act 2016)
Limiting the design scope limits a self‑builder’s motivation. It reduces the experience to one driven only by equity rather than a combination of aspiration and equity. We understand how to position a market offering at the right point between design control and design freedom. This balance maximises market attractiveness, supports confident sales and protects overall land value.
Section 106 obligations can require developers to deliver Custom Build housing as part of their scheme. To ensure that these plots are genuinely marketable and to assess demand and valuation accurately, specialist knowledge of the self build market is essential. Understanding the nuances of plot purchaser demands, price sensitivity, design expectations and delivery models is critical. We have track record of renegotiating the S106 terms with the LPA to allow for the feasible and successful delivery of Custom Build on SME and larger House-builder sites.
This is where our expertise becomes transformative. We make Custom Build sites deliverable, commercially viable and aligned with market demand, while supporting a structured sales methodology that helps achieve the highest possible plot values.
Why Custom Build?
The key motivation is simple:
1. You unlock a faster sales journey and maximise land value without taking on the risks of full development.
2. You retain full ownership of the land and sell directly to the plot purchaser, putting you in charge of sales values, methods and timescales.
3. By selling serviced plots, with an outline consent you will create a premium self-build experience, where purchasers buy land with planning approval and essential services connected to plot boundary at point of contract exchange, significantly de-risking their purchase and build journey while adding premium value to your land sale.
This approach not only accelerates transactions but also positions your land as a high-value, low-risk opportunity for buyers, while you retain control and avoid the complexities of construction.
Delivering Custom Build
A structured, de‑risked solution for Landowners & Developers
The WILMONTS team are the experts you can trust.
We offer comprehensive Design, Planning, and Project Management Services tailored specifically for Custom Build sites. Providing and green field‑to‑delivery for end user service designed to unlock the full potential of your land while removing the operational, planning, and financial risks typically associated with development.
Our services operate on a fee-for-service model, devoid of any tie-ins or additional charges related to land sales. We facilitate the assessment of appraisal scheme viability, manage surveys and reports essential for planning approval, and develop Design Codes, conceptual house types, and master plans for the site. We provide marketing and sales support, along with design, planning, and project management services for individuals engaged in Self Building.
1.
Advise & Appraise
Feasibilty and Intial Valuation
We conduct site visits to evaluate compliance with planning policy, assess local demand and carry out viability checks for the development.
We provide early guidance on plot valuations and offer financial insight to support informed decision‑making for developers.
We are specialists in appraising land and development proposals against Self Build requirements and real market demand, ensuring that the design, planning and commercial strategy align with how self builders actually buy and build.
2.
Design for planning
Site Plan, Design Code &
Concept House Types
Using our extensive knowledge of the Self Build and Custom Build market, we:
- Create practical multi‑plot site layouts that balance design quality with commercial viability and deliverability.
- Develop site‑specific concept house types that set a clear design direction while maintaining flexibility for self builders.
- Produce comprehensive Design Codes that support planning submissions and establish the framework for consistent, high‑quality site delivery.
3.
Outline Consent or S106 Obligation Support
Planning Submission
- We manage your planning application, typically and Outline Consent with Reserved Matters for the induvial dwelling designs.
- Manage surveys and technical reports to support planning applications.
- Ensure you avoid costly pitfalls such as unnecessary CIL liabilities and additional Stamp Duty, which can arise from incorrect contract structures or poor contract management.
Our Custom Build method creates a clear pathway for Landowners, provides vision and confidence for Planners, and unlocks new opportunities for Inspired Plot Seekers.
4.
Marketing support and sales materials
Marketing Collateral and Support
We create high‑quality marketing collateral, provide informed consultation to both seller and buyer, and deliver sales training for sales agents. This ensures all parties fully understand the nuances of Custom Build and are equipped to support successful plot sales.
- Market positioning and pricing strategy, including concept house type example pricing.
- Marketing collateral and promotional planning.
- Legal support and coordination through to land sale or plot disposal - we have template agreements, explainer materials and an established network of conveyancing firms that we work closely with to define the Custom Build obligations within the land sales agreements, safeguarding the wider development and the seller.
You may choose at this stage to sell the entire site, benefiting from the uplift in value generated by securing planning permission. If you decide to take this route, we work with a network of SME developers who invite us to bring forward new land opportunities. We can introduce your site to suitable buyers and support a smooth, well‑informed disposal process.
5.
Site Establishment
Site works - Safe access & Services to plot boundaries
We offer a consultancy and/or project management service to help you establish the Custom Build Site, ready for market.
- We provide cost guidance
- A network of trusted suppliers
- Project services
Depending on site conditions and location. As a general guide, you should expect to pay in the region of £30,000 to £40,000 per plot on a site with no abnormal constraints. We can guide you through each stage of the works, or take on full project management responsibilities and manage the entire process on your behalf.
6.
Plot Purchaser Support and Compliance
Self Builder Design, Planning & Compliance
As the authors of the site plan and design code, we are uniquely placed to deliver the architectural and design services required by individual Self Builders. While plot purchasers are not obligated to use our design and planning services, you may choose to make this a condition of sale. Doing so helps maintain continuity, ensures design quality, and supports coordinated delivery across the entire development.
Our involvement at this stage provides a direct link between the original design vision and the built outcome. We guide each Self Builder through the design and planning process, ensuring their home aligns with the parameters established for the site within the design code, while still offering the freedom for personalisation and creative expression.
Site‑Wide Compliance Management
Whether or not we act as the principal designer for individual plots, we can serve as the site’s compliance manager. In this role, we:
- Ensure each Self Builder appoints an appropriately qualified project manager.
- Oversee adherence to the design code, site rules and planning conditions.
- Provide consistent interpretation of the design framework across all plots.
- Help maintain visual cohesion, quality standards and construction efficiency.
This approach protects the integrity of the development, supports smoother project delivery, and provides reassurance to landowners, local authorities and plot purchasers that the site will be completed to a consistent and high standard.
Want to know how to deliver and value Custom Build?
Lunch & Learn
Lets arrange a meeting, in person or over teams.
Get in touch
E-mail: info@wilmonts.co.uk