Wooden fire door refers to the door frame, door leaf frame, door leaf panel made of wood or wood products, and the fire resistance limit reaches the specified door.

Fire doors are one of the facilities for building fire separation. Usually used on firewalls, stairwell entrances and exits or pipe well openings. It plays an important role in reducing fire losses.
In the design code for fire protection of high-rise civil buildings, fire doors are designated as A, B, and C. And the fire resistance limit is stipulated. Class A door is not less than 1.5 hours, Class B door is not less than 1 hour, and Class C door is not less than 0.5 hours.

Wooden fire doors are divided into two series, full board and half glass, and various specifications of single and double leaf.
Standard sizes:
The opening size and structural size of the wooden fire door shall meet the requirements of GB 5824 “Series of Door and Window Opening Dimensions for Buildings”.　The fireproof wooden door is a kind of plywood craft door, the best wood material is to use coniferous species. Plywood generally uses urea-formaldehyde resin five plywood, its appearance is similar to ordinary plywood craft doors, but fireproof wooden doors have higher requirements for materials.

It is very important to control the moisture content of wood (including plywood) used in fire-proof wooden doors. It can keep the door with proper clearance, normal operation and no cracking. At the same time, the wood needs to be fire-retardant and ready for use.

The core filler material plays a decisive role in the fire resistance performance of the fireproof wooden door. It should have the characteristics of low thermal conductivity, small volume and quality, good processing performance, etc. It is beneficial to improve the fire resistance level of the door = reduce the weight of the door, eliminate or reduce the initial deformation of the wooden door (Angle drop, warpage).

Fireproof wooden doors made of 32VL flame-retardant materials. Its fire resistance time reaches 68min, which greatly exceeds the 54min Class B standard and is close to the 72min Class A standard.

It is very important to choose the hardware (hinge, bolt, door lock, door closer, handle, etc.) of the fireproof wooden door. It must be matched properly to withstand the test of fire.

First: knock and weigh fire rated wood doors

According to experts, to distinguish the quality of fire rated wood doors, the first step is knocking and weighing. The fillings in the door are generally divided into solid and partial solids. The solid fillings are definitely heavy and the price is expensive; while the partial solids are relatively light and the price is relatively cheap.

Second: check the “sealing strip”

“Sealing strip” is directly related to the compactness of the door. The sealing strip is “hidden” in the contact part between the door cover and the door leaf, which is soft to the touch. Regular enterprises will add sealing strips to avoid the problem of a seam after closing. If the seal is not tight, the fireproof material will easily release formaldehyde, which is not up to environmental protection standards.

Third: Door covers are equally important

The material and quality of the door cover are also the key to environmental protection. Some businesses use different materials for door cover and door leaf. Real fireproof door leaf does not mean that real fireproof door cover will be used. If the actual fire door is made of MDF, because it does not contain fireproof fibers, it will easily foam when exposed to water, which will cause the door frame to deform. Therefore, when buying, ask whether the door cover and door leaf are a kind of material.

Fourth: understand environmental protection indicators

The harmful substances produced by fire rated wood doors mainly come from man-made fire-proof panels and paints. When consumers buy fire doors, they must understand whether their environmental protection indicators meet the standards: formaldehyde emission ≤ 1.5 mg/L, soluble lead ≤ 90 mg/kg, soluble cadmium ≤ 75 mg/kg, soluble chromium ≤ 60 mg/kg, etc. Fire doors with the characteristics of light weight, good rigidity, waterproof, anti-corrosion, insect-proof, sound insulation, heat preservation, and flame retardancy should be the first choice.

How to Purchase Doors and Windows from China: A Comprehensive Guide