Flat roof with secret gutter, Esher.
This flat roof uses a box gutter to collect run-off and discharge it into a down pipe.
This allows for a fascia without conventional guttering which improves the aesthetic of the roof.
Although internal gutters can be in some cases be regarded as a risk, these issues can be overcome using welded T-Prenne expansion joints and heating tapes to ensure the gutter flows freely.
This roof uses code 6 milled lead sheet and code 5 flashings to abutments.
Flat Roof , Dartford.
This project had to accomodate the architect and clients vision within the current specifications for a modern insulated home.
Tapered urethane insulation boards were used to achieve the fall of the roof, thereafter a series of man made boards and counter-battens were installed to achieve cross ventilation.
Ventilating of roofs is an area often overlooked when aiming to achieve high insulation standards. Ventilation is particularity important when working with man made timber boarding, lack of ventilation can lead to moisture build up or sweating, which in some cases can cause underside corrosion of the lead sheet.
The aim is achieve an air flow under the finished roof deck, using counter-battens to create an airflow void above the insulation. Eaves ventilation was used in this case to allow air to move freely under the drip edge on the tiled mansard roof and then through the roof void.
Pitched Bay Window, Canterbury.
The previous lead roof panels on this pitched bay window roof had failed due to lack of adequate fixings.
This is an area which is often overlooked when working with lead sheet, particularly on pitched roofs.
We decided to fit a series of smaller panels which would allow for adequate head fixings and ensure a longer lifespan.
Lead-welded clips were used to prevent windlift of the free edges of the lead sheet, whilst maintaining an expansion gap of 5mm to allow for thermal creep of the lead panels.
Our experience of this type of remedial work suggests the most common cause of lead sheet failure is under-fixing or in some extreme cases over-fixing.
Curved roof, Deal.
This roof was created to match an existing porch canopy on the property.
Hardwood curved rafters were used alongside tongue & groove boarding.
This approach was chosen primarily for the aesthetic but it also has constructional benefits.
The interlocking boarding achieved a uniform curve and provided greater strength over alternative modern materials.
We chose to use wood cored rolls which were steam treated to achieve the curve on this unique roof.
Dormer cheeks are vertically clad to achieve an weathertight solution as an alternative to weather-board cladding.
Lead soakers are turned up against the dormer cheek and dressed under each tile course.
Welted cladding is then dressed down over these soaker up-stands to weather the joint between the abutment.
In this case the lead sheet was returned into the dormer and turned against the back of the window frame to ensure a good weather seal.
Barrel Vaulted Dormer, Peasmarsh.
Curved roof dormer with lead clad cheeks.
The curved timber moulding performs two functions:
– creates a drip for the curved roof to ensure water runoff is thrown clear of cheek
– provides weathering to our copper ring shank head-fixings which secure the cheek cladding