Paul Gloria Meadows:
i took my volvo and flat trailer under a 11’ 2" bridge the other day to get into a factory. the only way in to it. the unit alone measures 13’ 3" so how does that work?
Was the bridge arched?
schrodingers cat:
Coffeeholic:
If you are going by what it says on the trailer and not measuring it then you are an idiot. The marking on the trailer isn’t worth the paint it is marked with, too many variables for it to be accurate.I hope this clarifies matters.
I don’t know what job you do but are you saying that if you changed units or trailers several times a day you would measure every one?
To be honest I would just build in a safety margin for the bridges I went under but probably 4" would be most likely ok as far as I’m concerned.
I wouldn’t measure everyone but you will get “an eye” for them and if the highest trailer in the fleet goes under, the rest certainly will.
I just dont drive under anything at 14’1 that is the highest trailer in our fleet, somedays i might be 13’10but i still dont break my 14’1 rule just in case i forget what trailer im pulling. Even if im out in one of our 18tonners i think they are 13’3 i still keep to 14’1 just out of habit.
Although getting these deckers in next year im going to have to rethink my 14’1 rule 
Driver
schrodingers cat:
Coffeeholic:
If you are going by what it says on the trailer and not measuring it then you are an idiot. The marking on the trailer isn’t worth the paint it is marked with, too many variables for it to be accurate.I hope this clarifies matters.
I don’t know what job you do but are you saying that if you changed units or trailers several times a day you would measure every one?
If necessary. I could be in any one of 4 or 5 different makes of unit at our place when I roll in for a shift and I know what each one runs at with the 3 or 4 different makes/height trailers we use having measured them in the past.
schrodingers cat:
To be honest I would just build in a safety margin for the bridges I went under but probably 4" would be most likely ok as far as I’m concerned.
I would rather know exactly, which could save me making a needless diversion because of a safety margin guesstimate. Takes no more than a minute to measure the height but could save miles of diversion.
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.
Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ■■■? 
Remember it depends on the sign. A circular sign will specify the maximum height of a vehicle allowed to proceed and will not necessarily be the height of the bridge above the road surface.
14 foot on a round sign and driving a 14 foot high vehicle you can proceed and will pass under the bridge.
14 foot on a triangular sign and driving a 14 foot vehicle and you are likely to scrape the roof of the trailer as in that case the 14 foot refers to the maximum headroom.
pavaroti:
I watched my tm measure my trailer load of roof trusses once, 15’9 he said. When I got to delivery site I found I had shaved off the top corners and slacken all my straps on a bridge with no height marking, minimum 16ft I thought these have to be?
Generally 16’ 6" before signs are needed.
Coffeeholic:
pavaroti:
I watched my tm measure my trailer load of roof trusses once, 15’9 he said. When I got to delivery site I found I had shaved off the top corners and slacken all my straps on a bridge with no height marking, minimum 16ft I thought these have to be?Generally 16’ 6" before signs are needed.
That’s a highway code rule isn’t it Neil? Good to know when you are on your test.
Wheel Nut:
Paul Gloria Meadows:
i took my volvo and flat trailer under a 11’ 2" bridge the other day to get into a factory. the only way in to it. the unit alone measures 13’ 3" so how does that work?Was the bridge arched?
Yes. I know it was the lowest part of the arch thats measured. Still ■■■’ed my pants when going under it. 
Coffeeholic:
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ■■■?
I was puzzled by Pat’s post too and do not know of any such regulation.
However, I was told once that bridge heights are measured from the pavement if there is a pavement running alongside the road beneath the bridge, and as a consequence there is about three inches more road clearance under most bridges than is signposted, and while I accept that this is a MMTM, from my own observations since being told this, it does seem to be the case.
streaky:
Coffeeholic:
pavaroti:
I watched my tm measure my trailer load of roof trusses once, 15’9 he said. When I got to delivery site I found I had shaved off the top corners and slacken all my straps on a bridge with no height marking, minimum 16ft I thought these have to be?Generally 16’ 6" before signs are needed.
That’s a highway code rule isn’t it Neil? Good to know when you are on your test.
No idea if it is in the Highway Code, I just know that is the limit for sign-age. Or at least it usually is, I’ve seen things marked higher than that.
Coffeeholic:
No idea if it is in the Highway Code, I just know that is the limit for sign-age. Or at least it usually is, I’ve seen things marked higher than that.
Every bridge in Spain has its height marked, even if it is 200m in height.
Coffeeholic:
streaky:
Coffeeholic:
pavaroti:
I watched my tm measure my trailer load of roof trusses once, 15’9 he said. When I got to delivery site I found I had shaved off the top corners and slacken all my straps on a bridge with no height marking, minimum 16ft I thought these have to be?Generally 16’ 6" before signs are needed.
That’s a highway code rule isn’t it Neil? Good to know when you are on your test.
No idea if it is in the Highway Code, I just know that is the limit for sign-age. Or at least it usually is, I’ve seen things marked higher than that.
it would be nice if they warned you before committing to the road that leads to it. how many of them have no warnings until a couple of hundred yards short of the low bridge? some of them warn you at the junction even if its a mile or 2 along the road, others dont warn you until you can see the ■■■■ thing
Someone on here with spare time should do an experiment get one of those laser things that measures distance. Measure a few bridges see what the tolerance is if any. Put a mmtm story to bed
Coffeeholic:
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ■■■?
Remember it depends on the sign. A circular sign will specify the maximum height of a vehicle allowed to proceed and will not necessarily be the height of the bridge above the road surface.
14 foot on a round sign and driving a 14 foot high vehicle you can proceed and will pass under the bridge.
14 foot on a triangular sign and driving a 14 foot vehicle and you are likely to scrape the roof of the trailer as in that case the 14 foot refers to the maximum headroom.
Can you give the source of this information?
It differs from what I’ve ever read, which is:
Circular signs are mandatory, vehicles higher than the shown height must NOT pass under.
Triangular signs are warning signs…
Reading forum postings about bridge heights you will find that most of the signs appear to be wrong one way or another.
I know of quite a few that are clearly wrong for one reason or another.
somerset bus driver:
Coffeeholic:
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ■■■?
Remember it depends on the sign. A circular sign will specify the maximum height of a vehicle allowed to proceed and will not necessarily be the height of the bridge above the road surface.
14 foot on a round sign and driving a 14 foot high vehicle you can proceed and will pass under the bridge.
14 foot on a triangular sign and driving a 14 foot vehicle and you are likely to scrape the roof of the trailer as in that case the 14 foot refers to the maximum headroom.
Can you give the source of this information?
It differs from what I’ve ever read, which is:
Circular signs are mandatory, vehicles higher than the shown height must NOT pass under.
Triangular signs are warning signs…
That’s exactly what I said.
Circular sign with 14 foot marked on it means a 14’ vehicle can proceed, a 14’ 1" vehicle cannot. Doesn’t matter if the actual structure is higher than the figure on the round sign, and it will be, unless your vehicle height is equal to or lower than the figure displayed you cannot pass the sign.
Triangular sign warns of the maximum headroom ahead, so 14’ on the sign and driving a 14’ vehicle you are likely to make slight contact.
The round signs don’t tell you the actual height of the bridge, and the clearance will be higher than the figure on the sign, The triangular ones tell you that clearance.
PinkLadyTrucker:
The Trailer says height is 4.2 M with a 1.2 M 5th WheelThat means the trailer alone is 9ft 11 plus the height of the 5th Wheel
Worse case scenario with a 5th wheel at 4ft 3inch 1295mm, The trailer would be 14ft 2 Inch
To hit the bridge with the trailer stated, the 5th wheel would need to be over 4ft 8 or 1420 mm
So was the air suspension up on the trailer? if so, Driver fault
Was the road resurfaced? Highways fault if signs not changed accordingly
Or was the trailer height incorrect at the start of journey? Not sure if Driver fault for not double checking, or Workshop fault, Probably Driver fault more so?
Yep.
I lost a bit of Roof on a M1 Bridge with a 15’8" Trailer.
When i doublechecked was the Trailer 16’3"
I didnt like the Company afterthen anymore
Coffeeholic:
somerset bus driver:
Coffeeholic:
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ■■■?
Remember it depends on the sign. A circular sign will specify the maximum height of a vehicle allowed to proceed and will not necessarily be the height of the bridge above the road surface.
14 foot on a round sign and driving a 14 foot high vehicle you can proceed and will pass under the bridge.
14 foot on a triangular sign and driving a 14 foot vehicle and you are likely to scrape the roof of the trailer as in that case the 14 foot refers to the maximum headroom.
Can you give the source of this information?
It differs from what I’ve ever read, which is:
Circular signs are mandatory, vehicles higher than the shown height must NOT pass under.
Triangular signs are warning signs…
That’s exactly what I said.
Circular sign with 14 foot marked on it means a 14’ vehicle can proceed, a 14’ 1" vehicle cannot. Doesn’t matter if the actual structure is higher than the figure on the round sign, and it will be, unless your vehicle height is equal to or lower than the figure displayed you cannot pass the sign.
Triangular sign warns of the maximum headroom ahead, so 14’ on the sign and driving a 14’ vehicle you are likely to make slight contact.
The round signs don’t tell you the actual height of the bridge, and the clearance will be higher than the figure on the sign, The triangular ones tell you that clearance.
I doubt that a 14 foot high vehicle willl scrape a 14 foot high signed bridge…examples please!
somerset bus driver:
Coffeeholic:
somerset bus driver:
Coffeeholic:
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ass?
Remember it depends on the sign. A circular sign will specify the maximum height of a vehicle allowed to proceed and will not necessarily be the height of the bridge above the road surface.
14 foot on a round sign and driving a 14 foot high vehicle you can proceed and will pass under the bridge.
14 foot on a triangular sign and driving a 14 foot vehicle and you are likely to scrape the roof of the trailer as in that case the 14 foot refers to the maximum headroom.
Can you give the source of this information?
It differs from what I’ve ever read, which is:
Circular signs are mandatory, vehicles higher than the shown height must NOT pass under.
Triangular signs are warning signs…
That’s exactly what I said.
Circular sign with 14 foot marked on it means a 14’ vehicle can proceed, a 14’ 1" vehicle cannot. Doesn’t matter if the actual structure is higher than the figure on the round sign, and it will be, unless your vehicle height is equal to or lower than the figure displayed you cannot pass the sign.
Triangular sign warns of the maximum headroom ahead, so 14’ on the sign and driving a 14’ vehicle you are likely to make slight contact.
The round signs don’t tell you the actual height of the bridge, and the clearance will be higher than the figure on the sign, The triangular ones tell you that clearance.
I doubt that a 14 foot high vehicle willl scrape a 14 foot high signed bridge…examples please!
It doesn’t matter if it scrapes it or not, the red circular ORDER sign is enough to cost you wages.
Coffeeholic:
Pat Hasler:
According to UK regulations every bridge must be atleast 3 inches higher than maked therefore a 14’6" bridge must have atleast 14’9" clearance.Have you got a link to this ‘UK Regulation’ or did you just pull that particular bit of BS from your ■■■?
I don’t know about it being a ‘regulation’ but it is a guideline for those involved in measuring bridge heights.
This is from a joint Network Rail, County Surveyors Society, Department for Transport guideline document.
Prevention of Strikes on Bridges over Highways
A Protocol for Highway Managers and Bridge Owners
Measuring headroom and determining signed height
3.1 The clearance under bridges spanning public roads in the UK, below which low bridge
signing is required, is 16’-6” (5.03m). All bridges with a headroom of less than this, at
any point over a carriageway, should be signed in accordance with the guidance
given in Chapter 4 of the Traffic Signs Manual (TSM)2 , section 7. This will, in all
situations, allow a minimum safety margin of 3” or 0.1m (these are not equivalent
values but are each determined in accordance with the measurement guidelines).
Additional guidance on the use of road markings to guide high vehicles at arch bridges
is given in Chapter 5 of TSM3. It is important to note that signing only relates to the
headroom over the carriageway. Footways and verges are not included and so related
chevrons or hazard markings must not extend beyond the limits of the carriageway.
3.2 The signed height at low bridges is referred to in this document as the (maximum)
safe vehicle height, as it represents the maximum height of vehicle/load combination
which can pass safely on the carriageway under the bridge without impacting on it,
allowing for vehicle (suspension) bounce, and safety tolerances. This is the height
which will usually be given to hauliers. Details of the actual measured minimum
headroom available and the wider headroom envelope at a bridge are for the use of
the highway authority in determining respectively the maximum safe vehicle height
and the potential for routing high vehicles around the network. High vehicles are
those which cannot pass safely under a bridge of 16’-6” (5.03m) minimum
headroom and so are those with vehicle/load combination greater than 16’-3” (4.95m)
high allowing for the minimum safety margin.