How to assemble a wooden greenhouse: the order that keeps it square
What decides whether a wooden greenhouse goes up in a weekend or fights you for a week? The base, and one habit: leaving the bolts loose until the whole frame stands. Timber that is fixed tight too early locks in every small error, and the door is where you notice. Here is the job in the order the NORDIC manual sets out, from the base to the last panel, with the checks that keep it square.
- Base first, to the plan. Build to the base size for your length, level in both directions, and check both diagonals.
- Loose, then tight. Lay the frame out and bolt it loosely; tighten only once the whole frame stands and lines up.
- Anchor it. The ground anchors in the kit are a condition of the structural warranty.
What has to be ready before the kit arrives?
A level base built to the size for your length, room to work all round, a site at least 2 m from buildings and fences, and two adults booked for the build.
The NORDIC manual opens with the base, because everything after it depends on it. Build to the base size on the plan for your length: for a 2 m NORDIC that is 2,800 × 2,250 mm, around a frame footprint of 2,580 × 2,048 mm, and our base guide has the figures for every length. The 3,294 mm diagonal on the plan belongs to the footprint, so compare it with the footprint’s diagonals, not the base’s. The width in the model name is not the size of your base. Clear and level about 0.5 m more than the base on every side, and more at the door end, so you can work right round the greenhouse with a barrow.
The manual also asks you to site the greenhouse at least 2 m from buildings and fences, away from overhanging trees, and to consider the snow load where you live. Two adults make the job far easier than one, and the product page puts it at one weekend with the base prepared in advance.
What should you check when the pallet arrives?
The polycarbonate, before the driver leaves. Look along every panel edge for cracks, dents and torn film, check the pallet corners, and write "damaged" on the delivery note before you sign if anything is.
Signing for a delivery as clean and reporting damage later makes a claim much harder, the manual warns. Photograph the whole pallet as well as the damage within 14 days and email it with your order number: we replace damaged components free of charge and cover the delivery. If you are building later, check on the day anyway. Then count the parts against the parts list. The manual’s quantities are for the longest configuration, so a shorter greenhouse uses fewer arches and sheets.
What tools do you need to put up a wooden greenhouse?
The NORDIC manual shows a cordless drill-driver with M8 and PH2 bits, a tape measure, a spirit level, a step ladder, a spade and gloves.
| Tool | What it does in the build |
|---|---|
| Cordless drill-driver, M8 and PH2 bits | Bolts the frame and drives the panel screws |
| Tape measure | Checks the base and both diagonals |
| Long spirit level | Keeps the base and frame level |
| Step ladder | Reaches the ridge, rafters and roof panels |
| Spade | Prepares the ground and sets the anchors |
| Gloves | Protects hands on brackets and panel edges |
Charge the batteries the night before and keep a sharp knife to hand. Ordinary hand tools cover the rest.
In what order does a wooden greenhouse go together?
Base frame, walls, gables and rafters, all bolted loosely; square it; then tighten, anchor it, fit the panels and finish with the doors and vents.
- Read the whole manual through before you open a single bag.
- Lay out the timber and brackets by their letters and lengths, as the parts list shows them.
- Build the base frame on the prepared base and check both diagonals.
- Raise the walls, gables and rafters, with the bolts done up loosely.
- When the whole frame stands, check it is square and level, then tighten every bolt.
- Fit the ground anchors as the manual shows; anchoring is a condition of the structural warranty.
- Fix the polycarbonate with the screws from the kit, following the numbered panel plan.
- Fit the doors and their handles as the manual shows, then check that the doors and the rear window open freely.
Each step is drawn and numbered in the manual, and the product page says each page of the guide carries a QR code for its video. The order matters more than the speed: a frame tightened before it is square will fight every panel after it.
| What you find | What to check |
|---|---|
| The frame sits close to the edge of the base | The base size against the frame footprint for your length |
| A later joint won’t line up | Level, squareness and whether earlier bolts were tightened too soon |
| More parts than a short greenhouse seems to need | The manual’s note that counts are for the longest configuration |
| The door or rear window catches | Frame alignment, then the fitting drawings |
Never use a screw to pull a panel into line: find the cause in the frame first. When the build is done, walk round it with the manual, check the fixings, the anchors and the moving parts, and photograph the finished greenhouse for your records.
How do the polycarbonate panels go on?
Last, once the frame is tight and anchored, with a screw and washer at every edge and the panels placed as the manual’s numbered plan shows.
NORDIC’s twin-wall polycarbonate is screw-fixed at every edge, with no spring clips. Follow the panel numbers in the manual and check the direction of the channels the manual marks before you drive the first screw. Where the roof sheet meets the ridge, the manual says to bend it over rather than cut it.
Who can build it if you can’t?
Anyone handy with a drill can follow the manual, and a local handyman or fencing contractor can quote from it. We don’t offer assembly, so send them the manual before they price the job.
Ask for a written quote that prices the base, carrying the kit from the kerb and the build separately. Our steel arch assembly guide covers the different job of building a Plot 3.14.
What keeps a wooden greenhouse in good order?
Re-treat the timber every two years with any UK-bought wood preservative and keep a dated record. That condition, with anchoring on a prepared level base, keeps the frame warranty in force.
The warranty reads: 10-year anti-rot frame warranty (conditional on re-treating timber with any UK-purchased wood preservative every 2 years) + 2-year polycarbonate panel warranty (manufacturer defects). A photo of the freshly treated frame makes a good record. The timber may be painted if you wish. Silvering, greying, tannin bleed and seasonal shrinkage are how slow-grown pine weathers, and the manual treats them as weathering rather than defects. Our maintenance guide covers the routine.
Don’t modify the design or hang loads from the frame. If a part fails, email the component code, a photo and your order number: parts are held for 10 years.
Quick answers about assembling a wooden greenhouse
It is far easier with two. Holding a wall upright while bolting it, and placing roof panels, both need a second pair of hands.
Not on firm, level soil, where the NORDIC’s ground anchors hold it. On concrete, paving or timber, fixings for those surfaces are bought separately.
So small misalignments can still be corrected. The manual asks you to tighten them only once the whole frame stands.
Note any damage on the delivery note, photograph it within 14 days and email us with your order number. Damaged components are replaced free.
What should you have ready?
The base finished and checked, the manual read, the parts counted, the tools charged and a helper booked.
Six things to have ready
Tick them off before the weekend. Your ticks stay on this device.
Read the manual before you order
The NORDIC page carries the manual, the base plan and the specification for every size. An expert can answer anything the drawings leave open.
What we checked for this guide
The steps, tools and checks come from the published NORDIC assembly manual and product page. Checked 20 October 2026.
- 01WaldenhausNORDIC assembly manual
Related guides
Written by the Waldenhaus team. We sell outdoor saunas and greenhouses and write these guides from manufacturer manuals, official guidance and our own product pages. Where your equipment manual says something different, follow the manual.