Why where there wooden doors in concentration camps?

1. What the physical evidence shows about wooden doors

Surviving material and post‑war documentation from Auschwitz–Birkenau record doors described as wooden but heavily reinforced and insulated—constructed of two layers of boards, metal fittings, and an inner insulation layer of “suprema” (wood shavings mixed with cement)—and are described in museum and memorial archives as gas‑tight for the application of Zyklon B in disinfection chambers and appropriate for similar sealing needs in gas chambers ^{[1] [2]}. The Auschwitz Memorial explicitly argues that extant wooden doors used in delousing installations proved wood could meet airtight requirements for Zyklon B use, countering claims that only metal doors could have been gas‑tight ^{[1] [2]}.

2. Testimony and archival references affirm wood was used in some crematoria

Oral testimony and contemporary reports collected by archives also record “hermetic” or “hermetically fitted” wooden doors in Birkenau crematoria, with witnesses describing strongly built wooden doors on underground mortuaries and crematoria installations—statements reproduced in National Archives summaries and camp investigation material ^{[3] [6]}. These firsthand and administrative sources are cited by historians and memorials to document the presence and function of wooden doors in specific buildings at Auschwitz‑Birkenau ^[3].

3. Why wooden doors were a plausible technical choice

Wood was abundant, easier and quicker to work with on large construction projects, and—when layered, sealed and reinforced—could be rendered effectively airtight for the purpose of holding Zyklon B vapors or other gases in localized chambers; memorial scholarship emphasizes that delousing chambers explicitly used wooden doors, demonstrating the method’s technical viability ^{[1] [2]}. Practical constraints of wartime construction, materials availability, camouflage needs (many homicidal facilities were disguised as bathhouses or delousing rooms), and site‑by‑site engineering decisions help explain material variation without undermining the broader historical conclusions about the camps ^{[1] [5]}.

4. Where metal doors appear and why variation matters

Not all camps or chambers used wood: Majdanek and other sites had airtight metal doors, and museum casts and documentation show metal bolted doors in some gas chambers, demonstrating that door material varied by camp, period, and engineering plan ^{[4] [5]}. Contemporary reports from Treblinka and other sites also describe iron or steel doors or fittings in certain installations, indicating that a single construction standard did not apply across the Nazi camp system ^{[6] [5]}.

5. The debate, denialist claims, and limits of the record

Denialist or revisionist arguments have seized on the presence of wooden doors to claim impossibility or inconsistency—asserting that wooden doors could not be “airtight” or that specific doors found post‑war cannot be definitively tied to homicidal use—but memorial institutions and archival testimony rebut this by documenting construction details and the known use of wooden doors in disinfection with Zyklon B, and by noting contemporaneous descriptions of “gas‑tight” wooden doors ^{[7] [1] [2]}. It must be acknowledged that the physical fabric of many crematoria was altered or destroyed during and after the war, so while sources show wooden doors were used and could be made airtight, the surviving record cannot prove the material of every door in every camp; statements here are limited to what the archives and memorial research document ^{[1] [3]}.