Waterproofing basement walls from inside, or interior waterproofing, can be done at any time, during or after construction.
Waterproofing using the interior method can even be done as part of a waterproofing basement DIY project fairly quickly. If you catch a leak at the first sign of a crack, your job will take a lot less time and require a lot less interior basement waterproofing systems and sealing products.
Sealing the interior of the basement uses sealants that are usually in liquid form that is sprayed, brushed, or rolled onto the walls and floors. After the sealant has been applied, an interior drainage system will benefit your attempt to keep your basement dry.
Interior drainage options come in a few different forms, but all will direct water away from the walls to keep the inside living space dry. Also, consider adding a dehumidifier or a dehumidifier product to reduce moisture inside.