BillyOh Bella 8x8 vs Petra 10x8 for a Garden Gaming Room (UK)

For a garden gaming room, the BillyOh Petra 10x8 is the better shell: its reverse-apex roof gives you a 2.47m ridge and enough floor for a desk, chair and a walkway, so a dual-monitor setup does not feel boxed in. Pick the BillyOh Bella 8x8 only when the plot or the access path cannot take a 10x8 footprint, or when you want the flatter, more contemporary pent-roof look. Be clear on one thing before you buy either: these are timber summerhouse shells, not turnkey insulated offices. Neither arrives power-ready, neither is insulated, and both need real damp control before a PC lives inside. Budget for a vapour barrier, foil insulation, an RCD-protected outdoor circuit and a dehumidifier on top of the sticker price.

Affiliate disclosure: we may earn from Amazon UK / eBay Partner Network links at no cost to you. Prices move constantly - always check the live listing before you buy.

Cost & price (UK, July 2026)

BillyOh prices swing hard with seasonal discounting, so treat any headline figure as a starting point rather than the number you will actually pay. Across the summerhouse ranges we tracked in July 2026, list prices and the typical 20-30% promotional discounts landed roughly like this:

• BillyOh Bella 8x8 (pent roof): list around £1,659, frequently discounted into the £1,150-£1,350 band during sales. The 11mm tongue-and-groove panelling and modern pent styling put it at the pricier end of the compact class. Check the live Bella 8x8 on Amazon UK or the Bella 8x8 on eBay, as retailer pricing diverges by a few hundred pounds.
• BillyOh Petra 10x8 (reverse apex): the Petra range lists from about £1,452, with 30% promotions dropping it near £1,016 on smaller sizes; the 10x8 typically settles in the £1,300-£1,600 range once you add the reverse-apex glazing. Compare the Petra 10x8 on Amazon UK against the Petra 10x8 on eBay before committing.

The bigger cost, though, is everything the price tag hides. A garden gaming room is not finished when the shell goes up. Realistic add-ons for a UK build:

• Insulation: foil-backed rolls and boards for walls, floor and roof. A run of BLOSTM foil insulation on Amazon or the equivalent foil insulation on eBay is the cheapest meaningful upgrade you can make, usually £40-£120 depending on coverage.
• Power: an outdoor RCD-protected circuit run by a qualified electrician is the single biggest line item, commonly £300-£700 for an armoured cable and consumer unit. For a compliant socket point, a Knightsbridge weatherproof RCD socket kit on Amazon (also on eBay) is a sensible starting part. If you are renting or want a temporary feed, a 25m RCD armoured outdoor extension on Amazon or the same armoured extension on eBay is a stopgap - not a substitute for a proper spur.
• Heating: a thermostatic panel heater keeps the room usable in winter and helps drive out condensation. A Devola 2000W glass panel heater on Amazon (or on eBay) runs around £80-£150.

Add it up and a £1,300 shell becomes a £2,200-£2,800 finished gaming room. The Petra costs a little more up front and gives you more of the thing that matters - internal volume - so on a pounds-per-usable-metre basis it is the stronger buy for a desk build.

Problems & drawbacks

Both models share the same underlying risks, because both are BillyOh timber kits assembled from tongue-and-groove panels. The reviews across Amazon UK, Trustpilot and garden-building forums are consistent, and the pattern is worth taking seriously before you spend four figures.

Quality control is inconsistent. The most common complaints are twisted, bowed or warped panels, splits and rough edges, and knots that fall out and leave holes. One Bella buyer described a near-£1,000 building that arrived soaked, with warped and split roof tongue-and-groove sections and missing pieces, and rated it worth about £300 of the price paid. That is not universal - plenty of builds go up fine - but the variance is high, so inspect every panel on delivery and photograph any damage before you sign.

Delivery and after-sales are the weakest link. Customers repeatedly report wrong or missed delivery dates, pallets left with no warning, and missing parts that take weeks to replace - sometimes with the replacements arriving in worse condition than the originals. Customer service is frequently described as slow and reluctant to compensate. Separately, the BillyOh affiliate programme was suspended in February 2026 for non-payment, which is a useful operational signal if you are spending a large sum and relying on the retailer to make good on problems.

Neither is weatherproof out of the box. The felt roofs can leak at joins and edges if you do not treat the timber and seal after assembly. BillyOh's own guidance is blunt: damp is almost always trapped moisture with nowhere to escape, so ventilation and a raised, well-drained base are essential. For a gaming room this matters more than for a garden lounge, because condensation rusts steel, corrodes connectors and kills electronics. Plan a vapour barrier, foil insulation, ventilation and a dehumidifier as non-negotiable, not optional extras.

Model-specific trade-offs. The Bella's pent roof is lower and flatter, which looks sharp but eats headroom and makes a tall-backed gaming chair feel cramped in an 8x8 footprint. The Petra's reverse apex buys you the 2.47m ridge and better light from the large front glazing, but the bigger base and delivery footprint need a wider access path and a properly level slab. Measure your side return before you order the 10x8.

Head-to-head

Who each is for

Buy the Petra 10x8 if you want a genuine garden gaming room rather than a hobby nook. The extra floor swallows a 140cm desk, a reclining chair and a small storage unit without the room feeling full, and the reverse-apex ridge means you can stand up, stretch and mount a monitor arm without ducking. It suits anyone planning a dual-monitor or ultrawide setup, or who wants the shell to double as a home office by day. If your garden has a level spot and a path wide enough for the base, this is the one. Pair it with our gaming room build kit for the desk, chair and cable-management shortlist, and see the studio setup guide for lighting and acoustic tweaks once the shell is up.

Buy the Bella 8x8 if your plot is genuinely tight, the access path is narrow, or you simply prefer the flat contemporary pent look. It is the right call for a single-monitor battle-station, a compact console corner, or a shared summerhouse that hosts a gaming desk without pretending to be a full office. Just go in knowing the low eave limits how you place a tall chair, and that the 8x8 internal footprint fills up fast once you add storage. If you might expand later, the Bella will feel small sooner than the Petra.

Buy neither if you need a warm, dry, plug-and-play office from day one. For that, an insulated garden-room system with factory glazing and a proper electrical spec is a different - and far more expensive - product category. Both BillyOh shells reward DIY effort; they punish the assumption that the shell is the finished job.

Best in class: the verdict