8x16 Greenhouse Plans

For this design the priced materials come to $4,522.27 at the store prices on this page, before sales tax and freight. The gravel bed is estimated apart, at $76 to $254. If you hire the build, published hourly rates times our hour estimate give $2,700 to $7,900 for labor. The total moves with the size, the glazing and the vents you pick in the designer.

We have not priced kits, so we cannot say which is cheaper for you. What we can say: building this 8x16 yourself from the plan costs $4,522.27 in priced materials plus your time. Compare that with a kit of the same floor area at its delivered price, and check what the kit's glazing and frame are rated for.

It depends on your town. The model building code exempts small one-story accessory buildings up to 200 sq ft, and this design is 128 sq ft, but many towns use a lower limit or treat greenhouses differently, and setbacks still apply. Ask your building department before you order materials.

This design uses 6 roof vents (28 sq ft of opening) and 7 side vents (26.3 sq ft): cool air comes in low and leaves near the ridge. We draw roof vents of at least 20% of the floor, the ASABE figure cited by extension guides. Wax-cylinder openers open the lids without power.

It is drawn for the 20 psf you see on this page. 8 mm twin-wall sheets are tabled by the maker to about 31 psf, so the planner turns red above that. Use the roof snow load your building department gives you, and clear heavy snow after storms.