The client had only recently moved into the property, and inherited four bridges over a small stream which ran the length of the garden. All of the existing structures were in a poor condition – either rotting boards or dangerous handrails. Having tried, without success, to get quotes from local builders (not interested/too small/not worth our while) they searched the Internet for prefabricated bridges, and became very confused with both quality and pricing guides.
They decided to try another route; a landscaper! What could they offer? Having visited the site and weighed up the problems – two bridges had to carry the lawn tractor and the others foot traffic only. I priced for all four units, and offered a discount if all bridges were installed during the same site visit, as I could work more efficiently, possible on one or more bridge each day.
Above all, they wanted a sensible price for a strong unit. Some of the prefabricated ones were several thousand pounds each, and were really too ‘good’ for a country cottage garden, where practicality had to meet common sense and a reasonable budget.
I opted for a very simple, but very strong method of construction, critically one that required no joints. Everything was pre-formed off site and ‘bolted’ together on site, by myself, without assistance.
The resulting bridges were indeed very strong – all were built using the same basic technique, two wider than the others to accommodate the tractor mower.
Essentially, the main structure was built using 100 x 225 x 2700mm softwood sleepers (all timber was pre-treated) sawn into three sections, held together with 100 x 100 x 2700mm timbers, with similar timbers used for cross members.
All cuts were made by hand using a £6.99 Barracuda hand saw. Fixings were all Timberlock screw/bolts for the main structure, and 150mm coach bolts for the hand rails.
Handrail uprights were 75 x 100mm with 50 x 100mm handrails. Decking was hardwood (all screw holes pre-drilled to avoid splitting) timber decking boards. A central strengthening timber was fixed to the length of the bridge to increase rigidity and prevent any flexing in the boards. NOTE; ensure that the side rails are perfectly vertical to prevent problems with upright handrails!
Costs? Materials for each bridge totalled £330.00 inc VAT. Cost of each unit £1,280.00 Time spent on constructing each bridge was three man days (24 hours) Gross profit on each unit was £950.00 including sourcing/collecting materials, or around £315.00 per day for labour.
(The weather was fine, there were no problems at all in installation, but there was ‘spare’ money should the project have overrun by a day or so for the complete ‘package’.)
I hope this does not upset the carpenter members out there! This simplified form or construction takes nothing away from the strength, relying on bolts and coach screws in place of joints, and I really do appreciate the skills involved in joinery. But the client got what they wanted; strong bridges built to a budget, suitable for a cottage garden.
