A loft conversion is one of the most cost-effective ways to add a bedroom or bathroom without extending your home's footprint, but getting it right depends on head height, roof structure and how the new stair fits into the existing layout. We design loft conversions across Kilmarnock, Ayrshire and Glasgow, including dormers, rooflights-only schemes and full structural rebuilds, and manage the drawings, structural calculations and building warrant submission from first survey through to an approved warrant.

Measured survey of your property, then design options with build costs discussed openly before detailed drawings begin.

Application prepared and submitted where needed - or written confirmation that permitted development covers your extension.

Full warrant pack submitted to your council, with every query answered through to approval.

Steels, openings and foundations designed with a chartered engineer and SER certified for your warrant.

An early, honest build-cost view so the design still fits your budget when builder quotes arrive.
Tell us about your project and we will give you an honest view of feasibility, approvals and budget - free.
Many loft conversions in Scotland fall under permitted development, but this depends on volume added, dormer position and whether your property is in a conservation area or has had permitted development rights removed. We confirm what applies to your specific property before design starts, so there are no surprises later. A building warrant is required regardless of the planning route, given the structural and fire safety implications of converting a loft.
Loft conversion design fees depend on whether a dormer is involved and the extent of structural work needed. We provide a fixed-fee quote after the initial survey, along with a realistic build cost range so you can weigh up the investment against the space gained.
CWJ Design Services provided a very professional service from start to finish. The drawings were clear, well thought out and handled efficiently for planning. Paul, the architectural technician, was knowledgeable, responsive and easy to deal with throughout. I would happily recommend them.

CWJ delivered clear, practical drawings for our structural wall takedown in Kilwinning. The planning and design process was handled efficiently, communication was good throughout, and the overall service gave us confidence to move forward with the project.

We used CWJ for our loft conversion and were very pleased with the service. The design was well considered, the drawings were produced promptly, and everything was explained clearly. The process felt organised throughout and made moving onto the construction phase much easier.
Popular Queries From Our Clients - Remove Any Uncertainty
It depends on size, position and your property type - many single-storey rear extensions fall under permitted development, but we confirm this for your specific property before design starts. Additionally, some lofts with dormer conversions may need planning permission.
Planning permission deals with whether a project is allowed in principle (size, appearance, impact on neighbours); a building warrant deals with whether it's built safely and to Scottish Building Standards. Most projects need both, but the routes are separate.
Most councils aim to determine a standard planning application within two months, though this can run longer depending on the local authority's workload and whether neighbour objections are raised.
This varies by council, but plan for several weeks to a few months depending on the complexity of the structural information submitted.
For anything involving a new opening, wall removal, extension roof or new build, yes - we coordinate this as part of our service.
An SER is the structural engineer's calculations and assessment confirming a proposed structural change is sound, submitted alongside building warrant drawings.
A completion certificate confirms the completed work meets the terms of the building warrant. You need one before a warranted project is signed off, and often before selling the property.
Some extensions qualify under permitted development, but this depends on your property's history, size limits and whether those rights have been removed - we check this before design starts.
Often not, if permitted development applies, but a building warrant is almost always required since the space becomes habitable.
Fees depend on project size and complexity. We provide a fixed-fee quote after an initial consultation, so costs are clear before you commit.
Yes, we offer a free initial consultation to discuss your project and give you an idea of design fees and next steps. Measured surveys are billable once a client agreement is in place.
We're based in Kilmarnock and cover East, North and South Ayrshire, Glasgow, Renfrewshire and Lanarkshire, including East Kilbride and Newton Mearns.
Yes, this is one of our core services, covering plot appraisal through to warrant approval.
We primarily work as architectural designers / technicians, which covers the vast majority of residential extension, conversion and new build design work without needing a registered architect. On occasion, we use consultancy Architect input for larger domestic & commercial projects.
Yes, we coordinate the structural engineering and building warrant needed to remove or alter load-bearing walls safely.
As much or as little as you'd like - most clients review concept options with us, then we handle the planning and warrant detail directly.
We review the reasons for refusal and, in most cases, can amend the design and resubmit, or advise on an appeal where appropriate. It should be noted that planning refusal rarely happens.
Yes, though these carry extra planning considerations - we flag this early if your property falls into either category.
Yes, we stay available through the build to issue any warrant amendments contractors need on site.
Get in touch by phone, WhatsApp or the contact form for a free consultation, and we'll talk through your project and next steps.

We believe great architectural design emerges from deep understanding of place, purpose, and the people who inhabit our designs.
Architectural Design & Drawings
Planning & Building Warrants
Structural Engineering
Cost Estimations & Feasibility
Construction Phase Support
Unit C, Block 10, Moorfield Industrial Estate, Kilmarnock KA2 0BA
07700 144853
Company No: SC885274
Copyright 2026. CWJ Architectural Design Services. All Rights Reserved.