weed/grass in-between patio slabs

[kofi2003uk]

hello,
got grass/plants growing in-between the slabs in my garden. have decided to fill in these spaces with concrete.
do i just buy building sand and cement from say B&Q.not sure if its called building sand.
also what should be the ratio of the mix ie cement and sand( if its simply called sand)?
thanks

 

[gcol]

3 parts building sand, 1 part cement.

 

[Deluks]

Put water in the joints first (carefully), let any water atop the slabs dry off then brush the mix in dry. Trying to slop wet mortar in the cracks could stain the patio.

 

[Thermo]

do that and youll be picking weeds out again in a years time.

clean out the joints, then mix as gcol says. get the mix damp so that you can squidge it in your hand without any water running out. then work it into the joints and point it of to finish it.

 

[kofi2003uk]

many thanks guys for your responses.most appreciated