Most of this generation of Commers did actually have front cab doors, depending on which firm built the cab and bodywork, but Alfred Miles and a few other body builders got rid of them - presumably for cost reasons.
When I sold the first D series Fords to Gloucestershire one complaint about these Commers - which we were replacing - was that access to the front seats was none too easy, and the door-less design did not help when it came to engine maintenance, either!
This Miles bodywork was originally designed for a Bedford chassis, which - before the TK series was introduced - had the front doors high above the front wheels rather than in front of them. It thus made sense to have the DPO and OIC enter from behind the wheel arch, as was the design adopted for the Green Goddess, among others.
This Miles body would have required a lot more modification to incorporate front doors in front of the axle, so both the Commers and the later Dennis F8s which had this cab had to do without front doors!
The first 49 Miles fire engines were Commers. The body was desisigned for Commers. The engine was under the floor and it was not at all difficult to get into the front seats. Some Miles Commers were built with cab doors for the driver and oic. There were also some Miles Dennis F8s with front doors.
The slant six Commer petrol engine was intended to allow access to the nearside curb for a lorry driver, to avoid exiting into the traffic stream - and to avoid the "dog house" which a vertical engine would have required; this was also considered a plus when it came to coach chassis, which Commer considered to be an important market too.
This did mean that a crew cab without front doors was feasible, but Rootes own crew cab (such as was to be found on Northumberland's Karrier hose tenders as well as numerous dust carts) was a four door.
My own local brigade, Darlington, operated two Commer pump water tenders - a Whitson and a Carmichael - and both were four door. These had the advantage that four 30 minute CA BA sets could be hung on a semi bulkhead behind the front seats, so crew members could don their sets on the way to an incident - an arrangement which also a feature of the brigade's Dennis F12 PE.
However, the two door Miles could only accommodate two sets, if the DPO and OIC were to access their seats from the rear...
When I sold the first D series Fords to Gloucestershire one complaint about these Commers - which we were replacing - was that access to the front seats was none too easy, and the door-less design did not help when it came to engine maintenance, either!
This Miles bodywork was originally designed for a Bedford chassis, which - before the TK series was introduced - had the front doors high above the front wheels rather than in front of them. It thus made sense to have the DPO and OIC enter from behind the wheel arch, as was the design adopted for the Green Goddess, among others.
This Miles body would have required a lot more modification to incorporate front doors in front of the axle, so both the Commers and the later Dennis F8s which had this cab had to do without front doors!
Added by Rob Johnson on 07 April 2020.