Spray Applied Fireproofing in Denver, Colorado
Andrex Insulation has been Denver's trusted SFRM specialist since 1988. We protect structural steel with UL-classified, spray-applied fireproofing on commercial projects across the Colorado Front Range — from high-rises and hospitals to schools and warehouses.
What Is Spray Applied Fireproofing (SFRM)?
Spray applied fire-resistive material (SFRM) is a cementitious coating that is spray-applied directly onto structural steel beams, columns, and metal decking to provide passive fire protection. The material creates a lightweight insulating layer around the steel that dramatically slows heat transfer during a fire, allowing the structural members to maintain their load-bearing capacity for the rated duration — typically 1 to 4 hours depending on the assembly.
In the construction industry, spray-applied fireproofing is often referred to simply as "Monokote" — a brand name that has become synonymous with the product category, much like "Sheetrock" for drywall. While Monokote (manufactured by Grace/GCP Applied Technologies) is one of the most recognized SFRM products, other widely used products include BlazeShield II from Isolatek International (Cafco). Regardless of the brand, all SFRM products used on commercial projects must be UL-classified and tested to meet the fire resistance requirements specified by the International Building Code (IBC).
The IBC requires structural steel framing in most commercial buildings to be protected with fire-resistive materials. The specific fire rating required — whether 1-hour, 2-hour, 3-hour, or 4-hour — depends on the building's construction type and occupancy classification. Type I and Type II construction, which includes most commercial high-rises, hospitals, and schools, typically requires 2 to 4 hour fire ratings on primary structural members. The thickness of SFRM applied to each member is determined by the specific UL design assembly, the steel section size (W/D ratio), and the required fire rating.
SFRM is the most cost-effective method of fireproofing structural steel in commercial construction. It is applied rapidly using specialized spray equipment, bonds directly to the steel substrate, and provides excellent thermal insulation without adding significant weight to the structure. For projects where an exposed steel aesthetic is required, intumescent coatings are used instead — but for the vast majority of commercial construction where the steel is concealed above ceilings or behind walls, SFRM is the industry standard.
Products We Use
We install only UL-classified fireproofing products from the industry's leading manufacturers. Every product is applied per the manufacturer's specifications and tested UL design assemblies to ensure full code compliance.
BlazeShield II
The most widely specified SFRM product in commercial construction. A Portland cement-based, spray-applied material manufactured by Isolatek International (Cafco). Excellent adhesion, low density, and proven performance in UL assemblies for 1 to 4 hour fire ratings.
Monokote MK-6
Grace/GCP Applied Technologies' flagship fireproofing product. A gypsum-based SFRM with high bond strength and abrasion resistance. MK-6 is frequently specified on projects requiring enhanced durability in high-traffic or exposed areas.
Certified Cafco Applicator
Andrex Insulation is a certified Cafco applicator, meaning our crews are factory-trained and authorized to install Cafco products. This certification ensures proper application technique and maintains the UL listing of every assembly we install.
Where Spray Applied Fireproofing Is Used
SFRM is required on structural steel in virtually every commercial building type. Here are the most common applications our crews handle across the Denver metro and Front Range.
Structural Steel Beams & Columns
Wide-flange beams, HSS columns, and built-up sections in office towers, hospitals, and institutional buildings.
Metal Decking & Floor Assemblies
Fluted metal deck with concrete fill — the most common floor assembly in commercial steel construction.
High-Rise Buildings
Type I-A construction requiring 3 or 4 hour fire ratings on columns and 2 or 3 hour ratings on beams and floor assemblies.
Hospitals & Healthcare Facilities
I-2 occupancy buildings with strict fire protection requirements to safeguard patients and staff.
Schools & Universities
Educational facilities (E occupancy) where fire ratings protect students and meet district requirements.
New Construction & Renovation
Both new steel erection and recoating or patching existing fireproofing during tenant improvements and seismic upgrades.
Our SFRM Installation Process
Every Andrex fireproofing project follows a proven six-step process designed to deliver code-compliant installations on schedule with minimal re-work.
Plan Review & Takeoff
Our estimating team reviews your structural and architectural drawings, identifies all fire-rated assemblies, determines the required SFRM thickness for each steel section based on the UL design number, and provides a detailed bid with quantities and schedule.
Surface Preparation
Before application, all steel surfaces are inspected and cleaned. If the steel has a galvanized or painted finish that may affect adhesion, we apply a bonding primer per the manufacturer's specifications. We also mask off areas that should not receive fireproofing, such as connection points and bolt heads designated by the structural engineer.
Application with Specialized Equipment
Our certified crews apply SFRM using calibrated spray equipment designed specifically for fireproofing. The material is mixed on-site to the manufacturer's specified water ratio and applied in passes to achieve the required thickness. Our operators are experienced at achieving consistent coverage on complex geometries including castellated beams, moment connections, and tight joist bays.
Self-Testing with Calibrated Thickness Gauges
After application, our crews self-test every area using calibrated thickness pins and gauges. We measure at the same grid points that third-party inspectors use, ensuring that thickness meets or exceeds the specified requirement across the entire floor. Any areas that are below spec are touched up immediately — before we call for inspection.
Third-Party Inspection Coordination
Once self-testing confirms all areas are at or above the required thickness, we schedule the third-party inspection. Because of our rigorous self-testing process, our first-pass inspection approval rate is exceptionally high — which means fewer delays and no surprise re-work on your schedule.
Punch List & Closeout
After inspection approval, we complete any remaining punch items, clean up our work area, and provide all required closeout documentation including product data sheets, UL assembly information, and thickness test reports. We stay responsive through the end of the project for any patching needed after other trades complete their work.
Why General Contractors Choose Andrex for SFRM
After 38 years and more than 7,500 completed projects, Andrex Insulation has earned a reputation as one of the most reliable fireproofing subcontractors on the Colorado Front Range. Here is what sets us apart.
38 Years of Experience
Founded in 1988, Andrex has fireproofed some of Denver's most significant commercial buildings including the Colorado Convention Center, Denver International Airport facilities, and major hospital campuses across the Front Range.
Self-Testing Before Inspection
We self-test every area with calibrated thickness gauges before calling for third-party inspection. This process catches deficiencies early, minimizes re-work, and keeps your project schedule on track.
BBB A+ Rated, EMR Below 1.0
Our Better Business Bureau A+ rating and Experience Modification Rate below 1.0 reflect our commitment to quality workmanship and jobsite safety on every project we take on.
Quick Mobilization
We maintain multiple experienced crews ready to mobilize within days, not weeks. When your steel is up and you need fireproofing started, we are ready to move.
Certified Cafco Applicator
Factory-trained and authorized to install Cafco products, ensuring proper application and maintained UL classifications on every assembly.
Trusted by Top GCs
We are a preferred fireproofing subcontractor for DPR Construction, Hensel Phelps, Mortenson, Swinerton, and other leading general contractors building across Colorado.
Spray Fireproofing Service Area
Andrex Insulation provides spray-applied fireproofing services throughout Colorado and the surrounding region. Our crews are based in Denver and regularly travel to projects across the state and into Wyoming.
Have a project outside our primary service area? Contact us to discuss availability and scheduling.
Frequently Asked Questions About Spray Fireproofing
What is spray applied fireproofing?
Spray applied fireproofing (SFRM) is a cementitious material that is spray-applied directly onto structural steel members such as beams, columns, and metal decking. It forms a lightweight insulating layer that slows heat transfer to the steel during a fire, helping the structure maintain its load-bearing capacity for the rated duration. The most common products used are BlazeShield II and Monokote MK-6, both of which are UL-classified for 1 to 4 hour fire-rated assemblies.
How long does SFRM installation take?
Installation timelines depend on the project scope, steel tonnage, and required fire rating thickness. A typical commercial floor (10,000-20,000 square feet of steel) can be completed in 2-5 days. Andrex crews are experienced at working within tight construction schedules and can mobilize quickly to keep your project on track. We coordinate closely with your GC to sequence our work around other trades.
What fire ratings can SFRM achieve?
Spray-applied fireproofing can achieve 1-hour, 2-hour, 3-hour, and 4-hour fire resistance ratings depending on the product used and the thickness applied. The required rating is determined by the building's construction type and occupancy classification per the International Building Code (IBC). Our team reviews your plans and specs to determine the exact thickness required for each assembly.
Do you self-test thickness before calling for inspection?
Yes. Every area we fireproof is self-tested with calibrated thickness gauges before we call for third-party inspection. This is one of the key reasons general contractors prefer working with Andrex — our self-testing process catches and corrects any deficiencies before the inspector arrives, which minimizes costly re-work and avoids schedule delays.
What areas do you serve?
Andrex Insulation serves commercial construction projects throughout Colorado and the surrounding region. Our primary service area includes Denver, Colorado Springs, Boulder, Fort Collins, Aurora, and the entire Front Range corridor. We also regularly take on projects in Wyoming. If your project is in the Rocky Mountain region, contact us for availability.
Are you a certified Cafco applicator?
Yes. Andrex Insulation is a certified Cafco applicator, meaning our crews are trained and authorized to install Cafco fireproofing products including BlazeShield II. This certification ensures that every installation meets the manufacturer's specifications and maintains the UL classification of the assembly. We also install Grace/GCP Monokote products.
Can SFRM be repaired or recoated?
Yes. Spray-applied fireproofing can be repaired or recoated when it has been damaged during construction by other trades, or when existing fireproofing in an older building needs to be brought back to spec. Andrex regularly performs patching and recoating work on renovation projects, tenant improvement work, and buildings undergoing seismic upgrades. We match the existing product and thickness to maintain the original fire rating.
Ready to Get a Bid on Spray Fireproofing?
Send us your plans and specs and our estimating team will provide a competitive bid with fast turnaround. Or call us directly to discuss your project.
Other Services
In addition to spray-applied fireproofing, Andrex Insulation provides a full range of commercial fire protection and insulation services.
Intumescent Fireproofing
Thin-film coatings that expand under heat to protect exposed structural steel with a clean, architectural finish.
Learn moreFirestopping
Code-compliant firestop systems for penetrations, joints, and openings in fire-rated walls and floors.
Learn moreSpray Insulation
Spray-applied insulation including Monoglass and K-13 for thermal and acoustic performance in commercial buildings.
Learn more