Protect what can’t be replaced—precision humidity control.
Irreplaceable collections can be permanently damaged by even small fluctuations in humidity and temperature. Museums, archives, and libraries rely on HVAC systems not for comfort—but for preservation, maintaining tightly controlled conditions around the clock while minimizing airborne contaminants. NovelAire’s AHRI-certified energy recovery wheels and advanced desiccant systems deliver precise, stable environmental control designed for preservation-critical spaces.
Why Collections Demand Precision Climate Control
Humidity: The Most Influential Variable in Preservation
Relative humidity is the single most critical environmental variable for collections preservation. Paper fibers, oil paints, leather bindings, photographic emulsions, wooden frames, and textile fibers are all hygroscopic — they absorb and release moisture from the surrounding air. When humidity changes, these materials expand and contract, creating internal stresses that accumulate over time. A A sustained spike in humidity can cause irreversible warping in wooden panel paintings, trigger bronze disease in metal artifacts, and accelerate acid degradation in paper archives.
The Dual Threat: Too Humid AND Too Dry
HIGH Humidity (Above 60% RH)
- Mold Growth — Mold spores are omnipresent and require only elevated humidity and an organic substrate to germinate. When RH exceeds 60%, mold can establish within 48–72 hours on paper, leather, textiles, and adhesives. Mold causes permanent staining, structural weakening, and releases acids that accelerate deterioration. Mold remediation in collections can cost hundreds of thousands of dollars.
- Metal Corrosion & Bronze Disease — Moisture combined with chloride ions triggers active corrosion in bronze, iron, and copper artifacts. “Bronze disease” is a cyclic corrosion process that, once initiated, continues to destroy the artifact even after humidity is corrected.
- Paper & Binding Degradation — High humidity accelerates acid hydrolysis and oxidation in paper — the chemical reactions that cause yellowing, brittleness, and eventual disintegration. Adhesives in bindings soften and fail. Gelatin-based photographic emulsions become sticky and adhere to adjacent surfaces (“ferrotyping”).
- Pest Infestation — Silverfish, booklice, and textile-eating insects thrive in humid environments. These pests feed on paper, starches, adhesives, and natural fibers — causing irreversible damage to books, documents, and textile collections.
LOW Humidity (Below 30–35% RH)
- Cracking & Embrittlement — Organic materials lose moisture and shrink. Paper becomes brittle and tears with minimal handling. Varnishes and paint layers develop craquelure (networks of fine cracks). Wooden panels, frames, and furniture crack along the grain. Parchment and vellum curl and distort.
- Binding & Adhesive Failure — Adhesives in book bindings, mounting tapes, and frame construction become brittle and fail. Leather covers desiccate, crack, and detach from text blocks.
- Dimensional Stress & Delamination — Composite objects (paintings on panel, inlaid furniture, layered photographs) consist of materials that shrink at different rates. Differential dimensional change causes delamination, lifting, and loss of surface layers.
Precision Climate Control — Sustainably
Museums and archives are traditionally large energy users because of tight humidity control requirements. HVAC systems must operate 24/7/365, often with redundancy. The outdoor air component — conditioning ventilation air to maintain pollutant control and pressurization — is the dominant energy cost. NovelAire’s AHRI-certified energy recovery wheels and desiccant dehumidification technology address this directly.
Key Benefits & Advantages
-Collections Protection
Maintain the ASHRAE Chapter 24 environmental classes required for long-term preservation. Prevent mold, corrosion, cracking, embrittlement, and chemical degradation by controlling the single most important variable: relative humidity stability.
-Precision Humidity Stability
Enthalpy wheels transfer moisture between airstreams — passively stabilizing indoor RH by pre-conditioning outdoor air. Reduce rapid humidity fluctuations that cause the most damage to hygroscopic materials. Support seasonal drift strategies for optimal preservation with minimal energy.
-Up to 85% Energy Recovery
Museums operating 24/7 at tight environmental tolerances pay enormous energy costs – ECWs can help reduce those energy costs by recovering up to 85% of the energy from the exhaust air.
-Pollutant Dilution & Filtration Support
Energy recovery makes it affordable to ventilate at the rates needed for pollutant control (ozone, SO₂, NO₂, VOCs) without prohibitive energy costs. Pre-conditioning outdoor air also reduces thermal stress on downstream gaseous-phase filters.
-Cold Storage & Film Archive Support
Desiccant wheels provide reliable dehumidification at cold vault temperatures (36–50°F) where conventional coils frost over. Maintain 30–40% RH in cold storage for cellulose acetate film, color photographs, and magnetic media.
-Sustainability & Institutional Stewardship
Reducing HVAC energy by 30–50% supports LEED certification, institutional sustainability goals, and the growing movement toward sustainable preservation practices. Lower energy consumption means more budget for conservation, exhibitions, and public access.
Energy Savings & Sustainability
Sustainable Preservation: Protect Collections AND Reduce Energy
Museums are traditionally large energy users — a mid-size museum can spend $200,000–$500,000+ annually on HVAC. The movement toward sustainable preservation, championed by the Getty Conservation Institute and reflected in ASHRAE Chapter 24’s seasonal drift strategies, recognizes that extreme energy consumption for rigid climate control is neither financially nor environmentally sustainable.
Collection Types & Environmental Requirements
- Paintings & Fine Art (Oil, Acrylic, Watercolor)
- Paper, Books & Documents
- Photographs & Film
- Metals, Bronze & Iron Artifacts
- Textiles, Costumes & Tapestries
- Audiovisual & Magnetic Media
- Natural History & Ethnographic Collections
Ready to Protect Your Collections with Precision Climate Control?
Whether you’re designing a new museum, upgrading an archive’s HVAC, or retrofitting cold storage for film preservation, our engineering team provides sizing, selection, and application support.