Doorway in supporting wall.

[GARYF123]

Hi,
I am about to tackle my first lintel and would appreciate some advice if possible.
I am wanting to create a standard size doorway on a breeze internal wall between the hallway and living room. I planned on using a 75mm x 100mm x 1050mm concrete lintel. Can anybody advise on this and also whether to use props to support ceiling joists (how many?) or strongboys?
If strongboys, how many and how high above proposed lintel position should i create holes for sb's to go through?

Many thanks in advance,

Gary.

 

[Chukka63]

Concrete lintels arent load bearing these days,the odd ones use to be but ive not found one lately.You will need a box lintel.If the joists rest on the wall in question, i get a couple of acrows and a scaffold board.Prop the scaffold board against your ceiling,spreading the load,make sure it goes past your acrows onto the next joist.
Cut out the hole for the lintel,placing it up to the blocks and dry packing underneath.This way you can immediately remove the acrows etc and get on fitting door lining and door etc.

 

[noseall]

P.c.c lintels are usually ok for most domestic standard size door openings.

However, if there is any point load to consider above the opening then a stronger alternative may need to be used, i.e. a pressed steel catnic type.

 

[Chukka63]

wasnt good enough for mr tosspot BCO on a job i did a few months back but what can ya say?.

 

[jm2000]

Concrete lintels arent load bearing these days,the odd ones use to be but ive not found one lately.You will need a box lintel.If the joists rest on the wall in question, i get a couple of acrows and a scaffold board.Prop the scaffold board against your ceiling,spreading the load,make sure it goes past your acrows onto the next joist.
Cut out the hole for the lintel,placing it up to the blocks and dry packing underneath.This way you can immediately remove the acrows etc and get on fitting door lining and door etc.

I agree. prop any ceilings around the doorway...see if you spot the direction of the joists above....any joists that run onto that wall.....that ceiling must be propped.

stitch drill a hole so a strongboy will fit in the centre of the doorway...just above where you are cutting out for the hieght of the lintel....100mm block, use a 100mm x 100mm concrete lintel, or catnic box section...but concrete is cheaper

Stitch drilling is where you drill a line of holes to knock the strongboy into. 8-10mm drill bit 8 is tight 10 is better

 

[Chukka63]

if the joists are on the wall i dont bother with other props for a single doorway.never had a prob even.

where do you get 100x100 conc lintels???

 

[jm2000]

if the joists are on the wall i dont bother with other props for a single doorway.never had a prob even.

where do you get 100x100 conc lintels???

Most good builders suppliers have them or can get themm to order...why

 

[Chukka63]

not stocked around here unless they hide them away somewhere away from all the other lintels

 

[noseall]

Agree with Chuck regards propping and 100mm square conker lintels. WTF!! Why on Gods gracious earth would a manufacturer make a lintel that did not correspond with any modern coursing.

A stout piece of 4" x 2" and a short length of wood will deal with any joist propping.

 

[Chukka63]

youre gonna do yourself no favours agreeing with me,im very controversial,lmao

 

[noseall]

im very controversial,lmao

I tend not to be.

 

[alittlerespect]

Reinforced precast concrete lintels are absolutely fine for your project - a standard lintel for such exercises used to be 4" wide x 3" deep (to match brick size x length, obviously dimenstions changed to suit the size of the opening in your case: door + lining 11/2" each side (bit of tolerance) + 4" bearing each side = 30" + 2.5" + 8" = 40.5" same as 1020mm therefore 1050mm lintel is fine.

Before making a start on the construction element - mark out on the wall the position of the lintel and the clear opening width for the door.

Most people would prop the existing blockwork by putting a pin through, an easier option is to use a 'jackall prop'(see HSS Hire - they should have instructions) basically chop out small hole insert jackall (on the opposite side of the wall from where you will be inserting the lintel! Tighten up jackall prop then cut out blockwork along line of lintel - place mortar bed on top of lintel and insert lintel - pack up lintel at each end at bearing points with pieces of slate to get a reasonably tight fit then point up the bearing at each end of lintel and point-in the top of the lintel (doesn't need to be pretty as it will eventually be plastered over) the previous bedding makes life a bit easier, then leave overnight. Next day carefully chop out blockwork to line of door opening - there you have your new door opening! The rest is down to you!!

With regard to the jackall prop you will only need 1No positioned at around the centre point of the lintel (you could go with no jackall prop but there is an element of risk associated with such antics, but I have to hold my hand up to the fact that I have followed this course of action, but if you know little about building I would not recommend it!

Regards

 

[jm2000]

not stocked around here unless they hide them away somewhere away from all the other lintels

Sorry my bad...didnt notice the typo...100mmx140x1200...anything but span lite... and the other point i was making was..if your a diy'er prop the lot....yes i would do like you and just prop what i need to...but if youve never attempted this before be safe and cautious

 

[Nige F]

Agree with Chuck regards propping and 100mm square conker lintels. WTF!! Why on Gods gracious earth would a manufacturer make a lintel that did not correspond with any modern coursing.

A stout piece of 4" x 2" and a short length of wood will deal with any joist propping.

Chinese

 

[noseall]

Chinese

If you please..