Pre-Engineered Metal Buildings in Boulder County

Snow load on a metal building roof is a number the jurisdiction hands you, and in Boulder County it changes with elevation. The county sets ground snow loads from its Ground Snow Load Map, drawn from a structural engineers' report on Colorado design snow loads, and it applies a snow importance factor for the most critical buildings based on site altitude. A building at the edge of the plains and a building up the canyon can look identical on a catalog page and need different frames.

That is the first thing we explain to an owner who is weighing a pre-engineered metal building. The system itself is efficient: a manufacturer engineers primary frames, secondary framing and cladding as a package, delivers them to the site and the erector bolts them together on a prepared foundation. What makes the project succeed here is matching the design criteria to the exact parcel, finishing the foundation and floor with care, and insulating the envelope so the building performs under the energy code.

Matching the package to the parcel

We begin with a site and criteria memo before any manufacturer quote is requested. It records the ground snow load from the county map, the design wind speed, the risk category, the frost depth, the seismic category and the drainage conditions, along with the building department's amendments. Quotes then compare like with like, and the owner is not surprised by a revised frame once the permit reviewer applies local criteria.

Next we coordinate the owner's use. Crane loads, mezzanines, hanging equipment, overhead doors, skylights and future expansion bays all change the frame, and it is far cheaper to add them to the engineering than to the finished building. We keep the manufacturer, the foundation engineer and the architect in a single set of comments so the package arrives complete.

Design criteria that vary by town

Unincorporated Boulder County takes basic design wind speeds for ordinary buildings from its own wind speed map, and it requires a soils or geologic report where landslide, rock fall, flash flood or soil creep may be present. The county's design criteria table lists a 30 inch frost line, although that table appears in the residential section, so we confirm the commercial value before foundations are designed.

Some mountain towns add their own constraints. Nederland, at 8,235 feet where State Highways 119 and 72 meet, has a long climate record showing very heavy snowfall, though the figure we have comes from an older record and should not be used for design. The county map governs. Lyons, at 5,341 feet at the confluence of the North and South St. Vrain Creeks, adds floodplain review. We cover the permit path in permitting and entitlements and maintain a checklist for each town.

Where metal buildings fit best

Metal buildings serve maintenance shops, equipment and vehicle storage, light manufacturing, retail shells, small warehouses, agricultural and public works buildings, and recreation structures. Their strengths are speed, flexible spans and easy expansion. The pre-engineered metal building category covers these uses, and mini-storage buildings are a common variant described under self-storage facilities.

They are a weaker fit where the owner wants heavy architectural expression, deep fire ratings in every wall, or a masonry look from the street. Even then a hybrid works: a metal frame with a masonry or panel face at the front. We discuss the choice openly and price the alternatives when the answer is not obvious.

What a metal building actually costs

The kit is only part of the price. Foundation and slab, erection, insulation, doors, trim, site work, utility connections and permit fees together can equal or exceed the package. Snow load, wind speed and building height raise the steel weight, and so does a clear-span frame with a wide bay. Insulation systems for energy compliance are a notable line item, because high R-values and thermal breaks are common requirements under current energy codes.

We prefer to price a building with and without options so the owner can see where money goes. Common add-ons are wainscot panels, sectional doors, translucent roof panels, gutters, and canopies. Where the site needs retaining or grading work, we price it under site development and utilities, because a steep lot can double the earthwork.

Fabrication then erection

The manufacturer's lead time starts after the engineering is approved, and it varies with demand. Meanwhile we prepare the site and pour the foundation, aiming to have anchor rods and slab edges ready when the first truck arrives. Erection follows in a regular sequence: columns and rafters, purlins and girts, bracing, roof and wall panels, then doors and trim.

In mountain locations, the seasonal window matters more. Snow can close canyon roads, and ground that has frozen cannot be excavated or compacted without cost. We plan foundations ahead of winter, then erect the frame in the first practical window. Owners with a hard opening date should place the order early.

Services that go with the building

A metal building is seldom just a metal building. Owners often add a clear-span interior, which we cover in clear-span rigid frame buildings, or a heavier frame for crane service. Public owners such as towns, fire districts and school districts use them for maintenance and storage, and government and public sector clients have procurement steps we handle with documented bids and submittals.

For sites with more demanding conditions, such as creek frontage in Lyons where the 2013 floods blocked every access route to the town, we plan access, drainage and flood elevation with the owner before the building is ordered. A prudent plan uses a higher slab, protected utilities and a haul route that remains open when the creek rises.

Send the parcel and the use

Tell us where the building will sit, what it needs to hold and when you need it open. We will return a criteria memo, a budget with options and a delivery sequence.

Questions Owners Ask

Can the same building be used in Nederland and on the plains?

Not without checking. The county ground snow load map varies with elevation, and a building at 8,000 feet needs a frame engineered for a much heavier roof than one at 5,000 feet. The package should be priced for the specific parcel.

How early should we order the building package?

As soon as the design criteria are confirmed and the permit path is clear. The manufacturer starts the lead time after engineering approval, so our goal is to approve engineering before the site work is complete.

Will a metal building meet the energy code?

Yes, with the right insulation and thermal breaks. The envelope has to meet the energy code that applies to the town, and in the city of Boulder the code is all-electric for most new commercial buildings. We coordinate wall and roof assemblies with the energy modeler.

Do you need a geotechnical report?

In most cases yes. The county can require soils or geologic reports where hazards such as flash flooding, rock fall or soil creep exist, and frost depth and bearing capacity affect the foundation. We include the report in the early budget.

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