When you apply for a homeowner loan (or any type of credit), the lender will carry out a hard search on your credit file. This will be recorded on your credit report, which may cause your credit score to dip temporarily. But, as long as you keep up to date with your monthly repayments, your credit rating will recover and should increase over time.
Please note, if you stop paying your loan, then your credit score will be affected, and your home may be put at risk.