Opinions sought on trowel mastic around a front door

[allegro]

Im looking for collective experience on using mastic around a front door. Currently one side has been done in concrete mortar and is cracked/falling out whilst the other side is in red sand mastic. This is also falling out and looks to have never set as it's still very pliable. For reference we moved in 6 years ago, it's a big project and I'm only just getting round to it.

Would prefer not to go the silicone route as I want a traditional finish and the gap in places is up to 13mm.

Anyone have any real world recommendations? A regular grey ish mortar colour would be ideal to suit the surrounding brickwork. Thanks all

[allegro]

Could I use window putty and paint the same as the door frame?

[geeks]

Pictures would probably help.

[allegro]

[dmsims]

Traditionally it would have been oakum and burnt sand mastic or lime mortar

[OutInTheShed]

You may want to add a beading or trim over the gap.
That would cover the mess on the bricks perhaps, if you can't get that clean.

Where you have a big gap, one thing which can work is to put a thick piece of cardboard in the gap and mortar up to that on the brick side, then later take the cardboard out and fill the nice regular gap with sealant of your choice. Not sure that's right in this case though?

[andy43]

If the frame is getting painted I’d use matching upvc trims and clear silicone to cover the lot after foaming the gaps.

[Chumley.mouse]

If your painting the door , chop out all the old , silicone all the gaps so no draughts , then a nice shaped wooden bead over it . Once painted it will look part of the frame.

Something like this ……

Cement will just crack again.

[Lotobear]

I would use compriband expanding tape and finish with polysulphide mastic

[wolfracesonic]

I’d go with Chumley’s suggestion, expanding foam in the gap then a nice, softwood scotia moulding painted to match the frame. If you really want to squeeze something out of a tube, go with a foam backer rod as Loto says, or expanding foam, then use an oil based mastic: polysulphide is great for masonry movement joints but is an absolute bd to apply neatly.

[Chumley.mouse]

Thats a bigger gap then i first thought. You could glue a strip of timber down it if its an evenish gap ?
That would give a better/ more solid base for the timber to fix to.

[T1547]

I used Everbuild Trowel Mastic around our timber front door a few years ago and is holding up well. Definitely more flexible than mortar and more in keeping with an older property than silicone.

[julianm]

A blowtorch & wire brush will shift most of the mastic from the bricks.
I've done mastic like that but reckon there are better materials available to do the job these days.
If you can add some long fixings through the frame it might be a good idea, as mastic which has hardened over the years will break up (like yours) if there is a small amount of movement when the door slams.

[Mr Whippy]

T1547 said:

I used Everbuild Trowel Mastic around our timber front door a few years ago and is holding up well. Definitely more flexible than mortar and more in keeping with an older property than silicone.

I used recently too (on a vent cowl), and used it to fill up to the natural stone so a big gap.
It takes a lot of work but it’s a really nice finish and looks like mortar but has that slight flexibility.


However, depending on area you live it can end up being removed by animals.
I’d done a big oak frame around a barn conversion window, and twice the lowest 60cm or so off the floor was removed.
The only sign of what it possibly was, was those sick balls with rodent skeleton bits in them, so assumed a local owl liked it for something?!