No, shouting distorts your voice and changes your intonation. You should face your family member and talk in a normal or slightly louder speaking voice.
Your family member probably cannot hear you, and most likely cannot understand you when you are at a distance. Even people with normal hearing have difficulty hearing people in another room. Please do not expect people to hear you from another room. Remember to get their attention before you start talking.
Some hearing-impaired people cannot tell the direction of a sound or voice. This is especially true when hearing loss is asymmetrical (not balanced). Sound localization is also an ability that diminishes with age.
A hearing-impaired person has difficulty in understanding words or parts of words. Your voice may be audible, but separate words may sound blurred. Rhyming or words that are similar such as: cat/cap, bread/thread, pool/cool, etc. are extremely difficult to distinguish. When your family member does not understand you the first time you say something, repeating the same words may not make it more clear. Consider rephrasing the sentence using different words which may be understood.
A hearing loss changes the relative loudness of sound. Your family member may not hear things that are soft to you. Sounds that are comfortable to you may be soft for your family member. Loud or sudden noises could seem just as loud to them or could even be uncomfortable or unsettling to them.
Hearing loss can make it difficult for your family member to judge the volume of his/her own voice because they aren’t able to hear themselves normally. Let your family member know when their voice may be too loud or too soft.
Some rooms have better acoustics than others. Empty rooms with hard walls may cause speech to echo, thus making it more difficult to hear and understand what is being said. Your family member also may have difficulty when out-of-doors, where the sound is dispersed in the air or when wind noise affects the use of hearing aids.
Yes, your family member may not hear as well as usual when tired or ill. This is because it may be more difficult to put as much effort into attempting to understand speech.
Even if you do not have formal training in lip-reading, we all make use of lip-reading (speech reading). This is by watching the speaker’s face and picking up on the visual cues. Try to converse in well-lit rooms. If glasses are needed, make sure they are used.
Background noise almost always interferes with the understanding of speech even for people with normal hearing. For people with hearing loss, it probably is the most difficult situation. Try to reduce the level of avoidable background noise when conversing. When in a restaurant, the person with a hearing loss should sit with their back against the wall; this helps reduce the interference of background noise. Also, sit at a table away from the kitchen or heavy traffic area.