Planning a Self-Build Spring 2026? Windows and Doors Edition

Spring is one of the busiest times of year for self-build projects. Especially in Scotland when we make the most of any dry weather we can.

One of the most common and costly mistakes we see on self-build projects is leaving windows and doors too late.

So, when should you order your glazing? And how early is early enough?

Here’s a clear, realistic guide to when to order windows and doors for build season.

Why Window Timing Matters More Than Most People Think

Windows and doors aren’t just a finishing item. They directly affect:

Structural openings
Airtightness and energy performance
Build sequencing and weather-tightness
Interior trades and overall build

Delays to glazing often cause a domino effect, pushing back plastering, flooring, kitchens, and even completion dates.

The good news? With the right planning, it’s completely avoidable.

Stage 1: Design Stage/ Production Drawings

When should this happen?

Ideally 4 – 6 weeks before you want to place your order

At this stage, you should have confirmed:

Final window and door schedules
Colours/finishes
Threshold details (especially for sliding doors)
Handings (the way the door opens)

Late design changes (even small ones) are one of the biggest causes of delays and cost increases.

Stage 2: Manufacturing Lead Times (The Reality)

Once your drawings are approved, the order is placed and manufacturing begins.

Typical lead times (guide only):

Standard windows: 8-10 weeks
Large sliding doors / minimal systems: 8–10 weeks
Bespoke colours or finishes: may add time

Spring and summer are peak production periods, so ordering early gives you:

Better scheduling
More flexibility

Top tip: Don’t wait until the roof is on to order by then, it’s cutting it fine.

Stage 3: Installation

Windows are usually installed:

After the structural shell is complete
Before internal plastering
Once openings are fully prepared and checked

Getting this right allows your build to become weather-tight, which is a major milestone.

From here:

Internal trades can begin
Airtightness detailing can be completed properly

Poor coordination at this stage often leads to rushed installs.

A Simple Timeline for Spring Self-Builds

Here’s a rough rule of thumb:

January–February: Finalise window designs
February–March: Place glazing order
March – April: Manufacture underway
May–June: Delivery & Installation on site

Every project is different, but this timeline keeps you ahead of the curve, not reacting to problems.

Why Early Planning Saves Money (Not Just Time)

Ordering windows early helps you:

Gives you more time to browse different products
Reduce site downtime
Get better performance outcomes
Maintain control of your overall budget

It also gives you time to properly consider:

Triple vs double glazing
Frame materials and finishes
Threshold and access details

All decisions that are much harder to change later.

Planning a Self-Build This Year? How Glass Worx Supports You Through Your Self-Build

At Glass Worx, we don’t see ourselves as window and door salespeople. We work as glazing consultants, supporting you at every stage of your self-build and beyond, if needed.

From early design discussions and technical decisions, right through to ordering, delivery, installation support and aftercare, we’re here to make the windows and doors side of your build as straightforward as possible.

We understand how challenging a self-build can be. There are countless decisions to make, tight timelines to manage, and plenty of pressure along the way. Our role is to reduce that pressure, offer clear and honest advice, and help you make confident decisions that suit both your home and your budget.

Most importantly, we aim to make choosing your windows and doors an enjoyable part of the process, not a stressful one, with ongoing support from people who genuinely understand how self-build projects work in the real world. We work with self-builders, architects, and contractors to ensure glazing is: