MegaDome HP · XP · XXP Modular Dome
The modular MegaDome workhorse — three oval-tube profiles from 30 to 90 ft clear span, engineered temporary or permanent, on the fastest install schedule in the MegaDome family.
- 30 – 90 ftClear span, 5 ft length increments
- Up to 3.2 kPaDesign snow (XXP profile)
- Temp / PermOBC-permanent or relocatable
- < 2 weeksTypical arch raise + tension
The MegaDome profile most Ontario operators are actually buying.
HP, XP and XXP share a common oval-tube modular MegaDome arch — the same hot-dip galvanized system, in three engineered variants tuned to snow zone, sidewall height and interior use. Building Depot specifies HP for the GTA, London and Windsor snow zones; XP for Barrie, Peterborough and Kingston where sidewall clearance for tandem trucks matters; and XXP for Ottawa, Muskoka and moderate Northern Ontario zones where design ground snow pushes past 3.0 kPa or the arch has to carry crane rails, lighting rigs or cable trays.
Every HP, XP and XXP arch is hot-dip galvanized to CSA G164 / ASTM A123 — the same corrosion-protection standard the Ministry of Transportation specifies for guide rail. That coating is why a permanent HP or XP salt shed carries a 50+ year expected frame life in Ontario's salt and freeze-thaw exposure, and why we won't supply an in-line galvanized or painted alternative for a corrosive use case.
The modular oval-tube system is the fastest MegaDome install format: a typical 40 × 100 ft salt shed, workshop or equipment shed is arch-raised and membrane-tensioned in under two weeks once the foundation is ready. That schedule is the reason municipalities routinely spec HP/XP for salt & sand storage — a building can be tendered in the fall and operating before the next winter season.
How to spec the right profile.
| Feature | HP | XP | XXP |
|---|---|---|---|
| Best snow zone | GTA, London, Windsor, Sarnia | Barrie, Peterborough, Kingston | Ottawa, Muskoka, mid-Northern |
| Typical span | 30 – 70 ft | 40 – 80 ft | 40 – 90 ft |
| Sidewall height | 8 – 14 ft | 10 – 16 ft | 10 – 16 ft |
| Design snow (Ss) | ≤ 2.4 kPa | ≤ 2.8 kPa | ≤ 3.2 kPa |
| Rigging / crane rails | No | Light | Yes (engineered) |
| Install speed | Fastest | Fast | Fast |
HP · XP · XXP — at a glance.
Foundation matches the use case.
Temporary construction cover on ballast, or permanent OBC salt shed on piers and push-walls — the modular arch pairs with the right foundation for the job.
Cast-in-place concrete piers
The standard permanent HP/XP/XXP foundation — frost-depth footings tied to a grade beam.
Reinforced slab-on-grade
Preferred for workshops, insulated shops and any building that needs a sealed floor.
Precast L-block push-walls (4–8 ft)
Small municipal salt sheds and mid-size sand storage.
Ballast blocks (temporary)
Temporary construction cover, seasonal storage and short-term relocatable use.
Helical / screw piles
Winter installs with no concrete cure window and environmentally sensitive ground.
Six ways Ontario operators are using the modular profile.
Salt & Sand Storage
Municipal salt sheds up to 70 ft — the most common HP/XP application in Ontario.
ExploreEquipment Storage
Farm, construction and municipal equipment under one modular roof.
ExploreAgriculture
Dry-cow, heifer and machinery cover for Ontario farms.
ExploreHay Storage
Round-bale and big-square hay cover with drive-through access.
ExploreWorkshops
Insulated modular workshops with radiant heat and full-height doors.
ExploreConstruction Storage
On-site material and equipment cover — relocatable when the job wraps.
ExploreFrom site coordinates to arch raise.
- 01
Site + use review
Latitude, longitude, exposure and importance category pulled per NBC/OBC — we recommend HP, XP or XXP based on real design loads.
- 02
P.Eng structural design
Modular arches, foundation and anchorage designed by an Ontario-licensed Professional Engineer.
- 03
Stamped drawings + permit
Sealed drawing set for municipal permit submission — even on temporary configurations that need one.
- 04
Foundation pour or ballast
In-house concrete crew for permanent builds; ballast anchors for temporary cover.
- 05
Arch raise + tension
MegaDome-certified crew erects arches and mechanically tensions the PVC skin — typical install under two weeks.
Why Building Depot specifies the modular MegaDome.
Where HP · XP · XXP sit in the Building Depot line-up.
MegaDome HHP Series
Step up to heavy-duty modular for Northern Ontario snow or corrosive process duty.
ExploreMegaDome XL Series
Wider clear span for hangars and warehouses — 90 to 130 ft.
ExploreMegaDome DB Series
Permanent truss-arch to 160 ft — salt sheds, riding arenas, aggregate cover.
ExploreMegaDome AR Series
Custom truss-arch to 200 ft — the widest MegaDome profile.
ExploreSalt Storage
The most-installed HP/XP application — municipal salt sheds.
ExploreWorkshop Buildings
Insulated permanent shops for farm, contractor and municipal use.
ExploreEngineering Services
Sealed structural + foundation drawings for permit.
ExploreFoundations
Piers, slab and precast push-walls — self-performed.
ExploreAll Building Models
Compare every MegaDome series head-to-head.
ExploreDownload the HP · XP · XXP technical package.
Modular arch spec sheet, foundation options, tender-ready salt-shed drawing pack and the Building Depot buyer's guide — all in one PDF.
MegaDome HP · XP · XXP — questions, answered.
Serving fabric building projects across Ontario
Quote your MegaDome HP · XP · XXP building.
Ontario engineering, foundation and installation on a single contract. No obligation.