Door Threshold / September 12, 2018 / Ambra Daoust.
Ive learned by the hard way of experience that its necessary to remove old existing jambs carefully. If directly fastened to masonry with cut nails jambs removal may break out the cinderblock unless the jambs are cut into short manageable lengths. An out of level concrete threshold step can be ground flat by a concrete cutting subcontractor or the door threshold can be adjusted by unscrewing and repositioning in the jamb by the amount out of level. Any attached brickmold and casing must be removed from the jambs to make installation easier with shimming. Also brickmold will probably have to be ripped in width to fit the overall brick opening width and height.
3. SECURITY Most folding doors will feature a high security locking system but many still use face fixed or flag hinges that can pose a possible security issue and allow the hinges to be removed from the outside when the door is closed. Some upvc bifold doors may also use an exposed gearing system that is accessible from the outside of the door when the door is closed which can also pose a possible security threat. You can eliminate these potential security problems by ensuring you choose a folding door that has fully concealed gearing and hinge fixings.
This calculation is based on the specification of the double glazing together with the profile design and dimensions to determine the insulation benefits of the door measured in U-values with the lower the value the better the insulation achieved. The minimum acceptable under current building regulations for replacement doors is a 1.8 U-value but some local authorities will insist on lower values particularly for new build extensions. 2. GLASS SIGHT LINES Another important consideration should be the sight line or width of door profiles between each panel of the folding sliding door as this will affect the visible glass area available when the door is in the closed position. Most bifold doors are designed with dedicated profiles to minimise these sightlines as much as possible but some timber and many upvc folding doors use wide chunky profiles that produce very broad sight lines in excess of 200mm wide that will ultimately spoil your view.
When youre satisfied that the door system is in the correct position drill through the thickest part of the hinge jamb with a regular drill at the hinges areas and then further drill into the cinderblock with a hammer drill. Drill the strike jamb in the same corresponding locations with the middle drilling positioned between the strike and deadbolt mortises. Countersink jambs holes to flush the masonry screw heads. It may be necessary to remove the door from the hinges for this step just remember to check the indexed jambs alignment to be sure nothing has moved. Remove shims and then remove door system from the rough opening. This must be done to install the plastic expansion sleeves into the holes drilled into the cinderblock.