We have just had the foundations + base done from a big company unfortunately during the cold no sorry freezing weather, I have had advise from a local builder saying the base and wall are badly frost damaged?? and probably foundations also. The company are telling me nothing wrong with foundations. What can happen if this is all frost damaged and they continue to build??
work should always be covered if frost is forcast,If not the frost will turn the mortar to powder.
Use a screwdriver and try to scrape the mortar out after it has been set for a couple of days,if its easy to do so ask them to redo the brickwork.