Clamshell Building Panels & LAMS Shelter Fabrication
APPF Inc. manufactures PVC Clamshell Building panels — replacement weathershells, new tent assemblies, LAMS components, and custom panel options for every system and application. From backyard pool enclosures to military aircraft hangars.
The Manufacturer Behind the Panels
Clamshell Buildings Inc. — the original manufacturer of these clear-span metal-framed tension fabric structures — is no longer in operation. But tens of thousands of their structures remain in service at military bases, airports, aquatic facilities, and commercial sites worldwide. Those structures still need panels.
APPF Inc. (American Pacific Plastic Fabricators Inc.) in Westminster, California is one of the few US manufacturers with the RF welding equipment, industrial sewing capacity, and material expertise to produce Clamshell Building panels at the scale and quality these structures demand. We fabricate replacement weathershells for aging structures and complete fabric envelopes for new construction.
Whether you need a single replacement panel for a System 50 shelter at a forward operating base, or a full set of insulated panels for a new System 80 pool enclosure, APPF is the source. Our panels are RF-welded and industrially sewn to specification — the same manufacturing processes used on the original structures.
Replacement Panels
Drop-in replacement weathershells for all major Clamshell Building systems — System 50, System 80, Series D, MegaDoor.
New Tent Assemblies
Complete fabric envelopes for new Clamshell Building structures. Full panel sets from end-wall to ridge.
LAMS / VLAM Components
Large Area Maintenance Shelter panels sewn and RF-welded to MIL-SPEC for US military and allied forces.
Custom Panel Options
Insulated, blackout, translucent, vented, and door panels. Any configuration, any system.
RF Welding & Industrial Sewing
In-house RF welding and industrial sewing — the two processes that define Clamshell panel quality.
Government & Defense Ready
ITAR registered, Berry Amendment compliant, CAGE 1NLJ3. Qualified for US government and military procurement.
Systems We Fabricate Panels For
APPF produces panels for all major Clamshell Building system configurations. If your structure is not listed, contact us — we can work from drawings or reverse-engineer from existing panels.
System 50
Standard aircraft & maintenance shelter
- Single and multi-bay aircraft hangars
- LAMS / VLAM deployable shelters
- Drone and UAV maintenance facilities
- Forward operating base shelters
Most widely deployed military variant. APPF fabricates replacement panels for all System 50 configurations including B-BBB and A-10 variants.
System 80
Large-span clear-span structure
- Commercial airport hangars
- Ice rink and aquatic facility covers
- Pool enclosures — residential to Olympic
- Large equipment storage
System 80 panels are the largest format APPF produces. Ideal for wide-body aircraft and large commercial applications.
Series D / MegaDoor
High-clearance door systems
- C-130 and wide-body aircraft hangars
- Facilities requiring full-width access
- Airport MRO facilities
- Military heavy-lift aircraft
APPF fabricates the full fabric envelope including the MegaDoor panel system for Series D structures.
LAMS / VLAM Shelters
Large Area Maintenance Shelters
- Deployable aircraft maintenance
- Forward operating base field shelters
- Rapid-erect military structures
- Allied nation military programs
LAMS (Large Area Maintenance Shelter) and VLAM panels are sewn and RF-welded to MIL-SPEC. APPF is one of the few US manufacturers with the equipment to produce these at scale.
Panel Options & Configurations
Not all panels are the same. APPF fabricates a full range of panel types to meet the specific requirements of your structure and application.
Standard PVC Panels
Heavy-duty coated PVC fabric panels — the core weathershell for all Clamshell Building systems. RF-welded seams, UV-stabilized, field-repairable.
Insulated Panels
Multi-layer insulated panel assemblies for climate-controlled facilities. Ideal for maintenance environments requiring temperature stability.
Translucent / Light-Admitting Panels
Allows natural daylight into the structure while maintaining weatherproofing. Popular for commercial and aquatic applications.
Blackout Panels
Zero light transmission for light-sensitive operations, photography, or security requirements. Full opacity RF-welded construction.
Vented Panels
Integrated ventilation panels for heat and fume management. Available in fixed and adjustable configurations.
Door Panels
Fabric door systems including roll-up, bi-fold, and personnel access doors. Custom-sized to structure opening dimensions.
Applications — From Pools to Airfields
Clamshell Building structures serve an enormous range of applications. APPF fabricates panels for all of them.
Residential & Commercial Pools
- Backyard pool enclosures
- HOA and community pool covers
- Hotel and resort aquatic facilities
- Retractable seasonal enclosures
System 80 panels are the standard for pool enclosure applications. APPF fabricates replacement panels for aging structures and complete new tent assemblies for new construction.
Commercial & Airport Hangars
- Regional and international airports
- FBO and MRO facilities
- Corporate aviation hangars
- Wide-body aircraft maintenance
Airport hangar applications demand the highest quality fabric panels. APPF's RF-welded seams and industrial sewing meet the structural and weatherproofing requirements of commercial aviation.
Military Bases & Defense
- CONUS and OCONUS air bases
- Forward operating bases (FOBs)
- Naval air stations
- Allied nation military programs (FMS)
APPF is ITAR registered, Berry Amendment compliant, and holds CAGE Code 1NLJ3. We supply LAMS panels and complete shelter fabric assemblies to US military and allied forces worldwide.
Industrial & Specialty
- Equipment storage and maintenance
- Ice rink covers
- Temporary event structures
- Missile and weapons enclosures
From missile enclosures at PMRF Kauai to ice rink covers, Clamshell Building structures serve a wide range of industrial and specialty applications. APPF fabricates panels for all of them.
Explore by Topic
Deep-dive pages for the two most common Clamshell Building needs — military LAMS shelter panels and replacement weathershells for existing structures.
LAMS Panels — Large Area Maintenance Shelters
MIL-SPEC fabric panels for LAMS and VLAM aircraft maintenance shelters. Berry Amendment compliant, ITAR registered, CAGE 1NLJ3. Predator shelters, FOB structures, FMS eligible.
LAMS panel details
Replacement Panels & Weathershells
Drop-in replacement weathershells for System 50, System 80, Series D, and MegaDoor structures. No OEM required. Fabricated from original drawings or reverse-engineered from existing panels.
Replacement panel detailsClamshell Building Gallery
Structures in service at military bases, airports, and commercial facilities — all using APPF-fabricated panels.
Why APPF for Clamshell Building Panels?
Producing Clamshell Building panels is not a job for a general fabric shop. These are large-format, structurally critical components that must be fabricated to precise dimensions with seam integrity that holds up to decades of weather exposure. The original manufacturer used RF welding and industrial sewing — and so does APPF.
With nearly 40 years of RF welding and industrial sewing experience, APPF has the equipment, the expertise, and the production capacity to deliver panels that meet the original specifications. We are one of the few US manufacturers who can produce these panels at scale — and we are the manufacturer that installation contractors and facility managers turn to when they need parts.
Working with Installation Contractors
APPF is the panel manufacturer. We supply the fabric components — the weathershells, door panels, end walls, and specialty panels — that installation contractors need to complete their projects.
If you are a contractor specializing in Clamshell Building installation, maintenance, or refurbishment, APPF is your manufacturing partner. We work from your drawings and specifications, or we can help develop specifications from existing panels.
We understand the timelines and quality requirements of government and commercial projects. Contact us early in your project planning to discuss lead times and specifications.
Frequently Asked Questions
Common questions about Clamshell Building panels, LAMS shelters, and APPF's fabrication capabilities.
Need Clamshell Building Panels?
Contact APPF Inc. to discuss your project. Provide the system model, panel type, and any available drawings or specifications — we will respond with a quote and lead time.
Also accessible at www.ClamShelters.com