How to Compare Garden Room Quotes: A Homeowner Checklist
Comparing quotes from different garden room companies can feel like comparing apples to oranges. One company quotes £25,000, another quotes £18,000, and a third quotes £32,000. How do you know whether you are genuinely comparing like-for-like, or falling into a trap where the cheapest quote becomes the most expensive project? The answer lies in asking the right questions and knowing where builders cut corners to make their headline figures appear more attractive. This checklist will help you navigate the process with confidence.
Section One: What Is Actually Included?
The most common way to make a quote look appealing is to leave things out. A quote that looks remarkable value at £18,000 may not include foundations, plastering, or electrics — items that can add £5,000 to £10,000 to the final bill. Before you compare any prices, you need to establish precisely what each quote covers.
Ask these questions of every company:
- Foundations: Are they included in the quote? What type of foundation is specified — steel screw piles, concrete pads, or ground screws? Is the foundation engineered to suit your specific ground conditions, or is it a generic assumption?
- Internal plastering: Does the quote include full skimmed plasterboard walls, or are walls left as bare painted MDF or timber? Full plastering adds a premium finish but costs more. Its absence is a tell-tale sign of a lower-spec build.
- Electrics: Does the quote include a consumer unit, sockets, lighting, and data points? Are these items priced per point, or is there a generous allowance as standard?
- Painting: Is the interior painted in a colour of your choice, or is painting left for you to arrange?
- Exterior groundworks: Does the quote cover any landscaping, paving, or trenching required to connect the room to your home’s utilities? Or is ground work an extra?
A genuine quote should itemise these elements clearly. If a company is vague about what is included, treat this as a warning sign. The cheapest quote is frequently the one with the most exclusions.
Section Two: Verifying Insulation Metrics
Insulation is the single biggest factor that separates a year-round usable garden room from a structure that is only comfortable for three months of the year. Yet it is also the area where builders obfuscate most effectively. You must ask for specific, verifiable numbers.
- Wall thickness and U-value: Ask for the exact wall build-up and the resulting U-value. A premium garden room should achieve a wall U-value of 0.18 W/m²K or better. This typically requires 100mm or more of PIR insulation within a substantial timber frame. If a company cannot provide a U-value, or quotes only a figure for “insulation thickness” without specifying the material, be wary. Different insulation materials have different performance characteristics — 50mm of PIR outperforms 100mm of mineral wool.
- Floor insulation: The floor must be insulated to the same standard as the walls. Cold floors render a room unusable in winter. Ask for the floor U-value and the insulation material and thickness.
- Roof insulation: Heat rises. A poorly insulated roof means expensive heating bills and a cold space. Ask for the roof U-value.
- Cold bridging: Ask how the builder prevents cold bridging — the transfer of cold through structural elements like timber studs. Thermal break tapes and careful detailing are the mark of a quality build. Cheap builders ignore cold bridging entirely, resulting in invisible draughts and cold spots.
- Glazing performance: Ask for the U-value of the glazing. Double-glazed aluminium frames with thermal breaks and low-emissivity glass are essential. Cheaper builds use residential-style uPVC frames or thinner, non-thermally broken profiles that undermine the entire thermal envelope.
If a company cannot or will not provide these numbers, they are not building to a premium standard. At RoomRise, we publish our U-values on every quote and explain exactly how we achieve them.
Section Three: Comparing Warranty Terms
A warranty is only as valuable as what it actually covers. Many garden room companies offer warranties that sound impressive but, on inspection, cover very little. You need to understand the difference between a structural warranty and a component warranty.
- Structural warranty: A true structural warranty covers the integrity of the building itself — the timber frame, the steel pile foundations, the EPDM rubber roof, and the overall weathertightness of the shell. This is the warranty that matters. RoomRise offers a 10-year structural warranty on every build, backed by our confidence in the engineering and materials we use. If the frame shifts, the roof leaks, or a foundation settles, we put it right.
- Component warranties: These cover individual items like door handles, locks, or glazing units. A manufacturer’s warranty on double glazing typically lasts 10 years, and a quality multi-point lock will carry a 10-year manufacturer backing. These are valuable, but they are not the same as a warranty on the building itself.
- Insurance-backed guarantees: Some companies offer insurance-backed guarantees (IBGs). These protect you if the company goes bust. They are worth having, but read the small print — they often cover only the deposit and the structural elements, not finishes or electrics. Manufacturer-backed warranties for glazing and hardware are standard on premium builds. Ensure that the warranty on offer is both comprehensive in scope and backed by a company with a track record of honouring it. A 10-year warranty from a business that has been trading for two years is not worth much.
Section Four: Evaluating Company Quality and Build Teams
The final layer of comparison involves the company itself. A garden room is a major investment, and you deserve to know who will be building it and what their track record looks like.
- In-house teams vs subcontractors: Does the company use its own employed teams, or does it rely on subcontractors? In-house teams are accountable to a single project manager and work to consistent standards. Subcontractors introduce variable quality and scheduling risks. At RoomRise, every person on your site is a RoomRise employee.
- Completed projects: Can the company show you a portfolio of completed projects? Not renders or marketing images, but real photographs of real builds. Look for consistency in quality and attention to detail.
- Reviews and testimonials: Read reviews on independent platforms. Look for patterns in the feedback. Consistent praise for cleanliness, punctuality, and communication is a strong indicator. A single negative review is not necessarily damning, but a pattern of complaints about delays, mess, or quality is a red flag.
- Company longevity: How long has the company been trading? A 10-year structural warranty is only valuable if the company is still around to honour it. Look for an established business with a proven track record in your region.
Section Five: Price Comparison Table
Once you have gathered all of this information, create a simple comparison table. Here is a template you can adapt:
| Feature | RoomRise | Company B | Company C |
|---|---|---|---|
| Price (incl. VAT) | £30,000 | £22,000 | £35,000 |
| Foundations included | Yes (steel screw piles) | No (extra cost) | Yes (concrete pads) |
| Wall U-value | 0.18 W/m²K | Not specified | 0.22 W/m²K |
| Full plastering included | Yes | No | Yes |
| Electrics included | Full package | Basic only | Full package |
| Warranty | 10-year structural | 5-year component | 10-year structural + IBG |
| Build team | In-house | Subcontractors | In-house |
| Build time | 10 days | 3-4 weeks | 14 days |
| 10-day build time. When you lay the comparison out like this, the seemingly cheapest option often looks very different. A £22,000 quote that excludes foundations and plastering, uses subcontractors, and offers only a component warranty may well cost you £30,000 or more by the time the project is complete — and deliver a lesser building. |
Conclusion
Comparing garden room quotes requires diligence and the willingness to ask direct questions. The goal is not to find the cheapest quote, but to find the quote that delivers the best value for a genuine premium build. Look beyond the headline figure. Check what is included, verify the insulation metrics, scrutinise the warranty terms, and evaluate the company behind the price.
At RoomRise, we welcome this level of scrutiny. We publish our specifications, itemise our costs, and stand behind our 10-year structural warranty. Book your complimentary design consultation today, and let us walk you through a quote that leaves nothing hidden.