Crumbling or failing mortar can be caused by a number of reasons.
Roof mortar crumbling.
1 mix 3 parts sand to one cement.
Your builder is wrong to say its fine if the mortar is crumbling away.
When the mortar on a verge crumbles or disappears then there is a risk of leaks from water being blown into the roof space.
Roof cement is primarily used to hold roof tiles hip tiles and ridge tiles securely in place it also keeps out rainwater.
The temperature change that comes with the seasons can also mean the swell and contracting of the mortar.
In most cases a crumbling.
If we re talking about common roofing jobs like pointing a chimney laying ridge tiles or flaunching the top of a chimney i would recommend a 3.
Failing mortar can usually be attributed to a lack of carbonation of the lime within the mortar meaning that the mortar will have little if any strength.
How much cement in a roof mortar mix.
This is a beginners guide to pointing up.
This is a great concern and something that highlights the need for a better understanding about what it takes to create a long lasting and top quality mortar.
The fact that it is very porous means that it can hold water.
The roof verge will need to be rebedded with mortar.
At the end of 2018 there were media reports of several new build homes suffering from crumbling mortar between the bricks.
This is generally a straightforward thing to do.
The correct mix ratio is 3 parts sand to 1 part cement this is much stronger than bricklayers use 5 1 as the cement on the roof must withstand more driving rain than a typic.
So what are the causes of crumbling mortar.
This not only causes cracking but it can also cause crumbling as the mortar denigrates.