Hertfordshire Conservatory Supply
Conservatory sizing and specification guide illustration

Conservatory Sizing Guide

conservatory sizing guide - Order the Right Size, First Time

Our experienced conservatory specialists take the guesswork out of sizing and specification. Tell us your requirements and we'll make sure everything fits your build perfectly.

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Why Getting the Size Right Matters

One of the most common concerns we hear from builders and homeowners alike is: "What if I order the wrong size?" It's a fair worry — but it's one we've built our entire service around solving. At Hertfordshire Conservatory Supply, our specialists review your requirements before anything is confirmed, so you can order with complete confidence.

Whether you're a builder working to a set footprint or a homeowner with a rough idea of what you want, this guide walks you through the key measurements and decisions you'll need to make — and explains exactly how we help you get them right.

How to Measure for Your Conservatory

  1. 1

    Measure the External Width

    Measure the full width of the wall opening or the proposed external footprint where the conservatory will sit. Include any returns or projections. Take this measurement at ground level and again at eaves height to check for any variance.

  2. 2

    Measure the External Projection

    This is how far the conservatory will extend from the house wall. Measure from the outside face of the house wall to the intended front edge of the conservatory. Account for any existing step, patio, or slope that may affect the base level.

  3. 3

    Note Your Ridge and Eaves Heights

    Measure from finished floor level to the underside of the existing window or door lintel (eaves height), and estimate your desired ridge height. These figures determine the roof pitch and frame specification — our team will advise on standard pitch options.

  4. 4

    Identify Your Wall Opening

    Note the width and height of the existing door or window opening through which the conservatory will connect to the house. This affects the threshold detail, the dwarf wall or full-height frame design, and how the internal flow will work.

  5. 5

    Send Us Your Figures

    Once you have your measurements — even rough ones — send them to us. Our conservatory specialists will review everything, flag any potential issues, and confirm the exact specification before your order is placed.

What Our Specialists Check Before You Order

Every quote goes through a specialist review. Here's what we look at to make sure your specification is correct.

Roof Pitch & Glazing Fit

We confirm that your ridge and eaves heights produce a viable roof pitch, and that the glazing panels specified will span correctly without any custom cutting surprises on site.

Dwarf Wall vs Full-Height Frames

We advise on whether your design calls for a dwarf wall with PVC or aluminium frames above, or full-height glazed frames — and make sure the brickwork and frame components are matched correctly.

Base & Foundation Compatibility

We review your base specification against the conservatory footprint to ensure the supplied components sit correctly on your planned foundation, whether that's a concrete slab, piers, or an existing patio.

Door & Window Placement

We check that door and window positions within the frame design are structurally sound and that all opening sizes are achievable within the system, avoiding costly amendments after delivery.

Common Sizing Mistakes — Caught Early

From forgetting to account for guttering overhang to misreading external versus internal dimensions, our team spots the errors that cause problems on site — before anything leaves our warehouse.

Full Specification Confirmation

Before your order is placed, you receive a clear written specification summary covering every component — so you know exactly what's coming and can plan your installation with confidence.

Expert Guidance Included

You Don't Need to Be a Conservatory Expert — We Are

Many of our customers come to us with rough ideas, not precise drawings. That's completely fine. Our conservatory specialists have years of experience translating approximate requirements into accurate, buildable specifications. We ask the right questions, identify what you may have missed, and confirm everything before a single component is ordered.

  • Guidance available for both trade builders and homeowners
  • No need for architectural drawings — measurements and photos are enough
  • We flag potential planning or building regulation considerations
  • Advice on standard versus bespoke sizing to keep costs down
  • All guidance provided free of charge as part of your quotation
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Conservatory specialist reviewing sizing measurements with a customer

Sizing & Specification: Frequently Asked Questions

What measurements do I need before I contact you?
At a minimum, we need the external width and projection (depth) of the proposed conservatory, plus the eaves height. Even approximate figures are a useful starting point — our specialists will guide you through anything that's missing.
What if I'm not sure whether my measurements are internal or external?
Just tell us how you've taken them and we'll convert as needed. It's one of the most common points of confusion and something our team handles on every quote.
Can I order a non-standard or bespoke size?
Yes. Our system accommodates a wide range of sizes. Where a bespoke specification is required, we'll advise on lead times and any cost implications upfront, so there are no surprises.
Do I need to provide a drawing or plan?
No formal drawing is required. A clear set of measurements and, if possible, a few photos of the proposed location are usually sufficient for our specialists to work with.
What if my measurements turn out to be wrong after delivery?
Our pre-order specification review is specifically designed to prevent this. We double-check your figures and confirm the specification in writing before anything is dispatched. If an error is identified after the fact, contact us and we'll work to resolve it as quickly as possible.
Does the sizing guide apply to both PVC and aluminium systems?
Yes. The measurement principles are the same across both systems. Our specialists will advise on any system-specific tolerances or details that are relevant to your chosen material.
How long does the specification review take?
In most cases, we turn around a reviewed specification and quotation quickly. Our team will confirm a timescale when you submit your requirements.

Ready to Get Your Specification Confirmed?

Send us your measurements and our conservatory specialists will review everything, answer your questions, and provide a free, accurate quotation — with nationwide delivery included.

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